# Critical Minerals and U.S. Public Policy

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/crs%3AR45810

## Record

- **Collection:** Congressional research report
- **Document type:** CRS Report
- **Published:** June 28, 2019
- **Citation:** R45810

## Text

Critical Minerals and U.S. Public Policy
Marc Humphries
Specialist in Energy Policy
June 28, 2019

Congressional Research Service
7-....
www.crs.gov
R45810

SUMMARY

Critical Minerals and U.S. Public Policy
President Trump and various U.S. lawmakers have expressed concerns about U.S.
reliance on critical mineral imports and potential disruption of supply chains that use
critical minerals for various end uses, including defense and electronics applications.
Chinese export quotas on a subset of critical minerals referred to as rare earth elements
(REEs) and China’s 2010 curtailment of REE shipments to Japan heightened U.S.
vulnerability concern.

R45810
June 28, 2019
Marc Humphries
Specialist in Energy Policy
-re-acte--@crs.loc.gov
For a copy of the full report,
please call 7-.... or visit
www.crs.gov.

In December 2017, Presidential Executive Order 13817, “A Federal Strategy to Ensure
Secure and Reliable Supplies of Critical Minerals,” tasked the Department of the Interior to coordinate with other
executive branch agencies to publish a list of critical minerals. The Department of the Interior published a final
list of 35 critical minerals in May 2018.

The concern among many in Congress has evolved from REEs and REE supply chains to include other minor
minerals and metals that are used in small quantities for a variety of economically significant applications (e.g.,
laptops, cell phones, electric vehicles, and renewable energy technologies) and national defense applications.
Also, as time passed, concerns increased about access to and the reliability of entire supply chains for rare earths
and other minerals. Congressional action (e.g., National Defense Authorization Act for FY2014, P.L. 113-66) has
led to the acquisition of REEs and other materials for the National Defense Stockpile. In 2017, the United States
had no primary production of 22 minerals and was limited to byproduct production of 5 minerals on the critical
minerals list. In contrast, the United States is a leading producer of beryllium and helium, and there is some U.S.
primary production of 9 other critical minerals. China ranked as the lead global producer of 16 minerals and
metals listed as critical. Although there are no single monopoly producers in China, as a nation, China is a
dominant or near-monopoly producer of yttrium (99%), gallium (94%), magnesium metal (87%), tungsten (82%),
bismuth (80%), and rare earth elements (80%).
The United States is 100% import reliant on 14 minerals on the critical minerals list (aside from a small amount of
recycling). These minerals are difficult to substitute inputs into the U.S. economy and national security
applications; they include graphite, manganese, niobium, rare earths, and tantalum, among others. The United
States is more than 75% import reliant on an additional 10 critical minerals: antimony, barite, bauxite, bismuth,
potash, rhenium, tellurium, tin, titanium concentrate, and uranium.
The current goal of U.S. mineral policy is to promote an adequate, stable, and reliable supply of materials for U.S.
national security, economic well-being, and industrial production. U.S. mineral policy emphasizes developing
domestic supplies of critical materials and encourages the domestic private sector to produce and process those
materials. But some raw materials do not exist in economic quantities in the United States, and processing,
manufacturing, and other downstream ventures in the United States may not be globally cost competitive.
Congress and other decisionmakers have multiple legislative and administration options to weigh in deliberating
on whether, and if so how, to address the U.S. role and vulnerabilities related to critical minerals.

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Contents
Introduction ..................................................................................................................................... 1
From 2010 to Present ................................................................................................................ 2
Congressional Interest ............................................................................................................... 5
The Scope of This Report.......................................................................................................... 6
Brief History of U.S. Critical Minerals and Materials Policy ......................................................... 6
The Modern Day Stockpile ....................................................................................................... 7
Initiatives and Actions on Critical Minerals .................................................................................... 8
Development of the Critical Minerals List ................................................................................ 8
Other Federal Critical Minerals Actions ................................................................................... 9
Department of Energy ......................................................................................................... 9
Department of the Interior ................................................................................................ 10
Department of Defense ..................................................................................................... 10
White House Office of Science and Technology Policy .................................................... 11
Supply: Critical Minerals Production and Resources .................................................................... 12
Production/Supply ................................................................................................................... 12
Production of Minerals and Mineral Resource Potential on Federal Land ....................... 12
Byproduct Supply ............................................................................................................. 13
Global Mineral Production ............................................................................................... 13
Secondary Recovery of Critical Minerals in the United States ............................................... 18
Reserves and Resources .......................................................................................................... 20
U.S. Critical Mineral Reserves and Resources ................................................................. 20
Global Critical Mineral Reserves and Resources ............................................................. 21
Mineral Exploration ................................................................................................................ 26
Locations and Minerals Being Explored........................................................................... 26
Demand: Critical Mineral End Uses and U.S. Import Reliance .................................................... 27
Demand for Critical Minerals ................................................................................................. 27
U.S. and Global Demand .................................................................................................. 28
Demand for Critical Minerals in China............................................................................. 28
U.S. Imports of Strategic and Critical Minerals ...................................................................... 29
Materials Analysis of Critical Minerals Content in Finished Products and Systems .................... 34
Lithium-Ion Batteries .............................................................................................................. 34
Solar Energy Arrays and Wind Technologies .......................................................................... 35
Permanent Magnets ................................................................................................................. 36
Materials Review of Wind and Solar Energy Systems ............................................................ 36
Materials for Wind Energy................................................................................................ 36
Materials for Solar Energy ................................................................................................ 38
Selected Supply Chain Analysis .................................................................................................... 38
Rare Earth Elements................................................................................................................ 39
REE Supply....................................................................................................................... 39
REE Supply Chain ............................................................................................................ 39
Tantalum.................................................................................................................................. 40
Tantalum Supply ............................................................................................................... 40
The Tantalum Supply Chain ............................................................................................. 42
Current Policy Framework ............................................................................................................ 43
U.S. Mineral Policy ................................................................................................................. 43

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General Mining Law of 1872: Mining on Federal Lands ................................................. 44
Federal Land Management and Mineral Development: Regulatory Framework for
Mineral Development on Federal Land ............................................................................... 45
Federal Land Policy Management Act .............................................................................. 45
Withdrawals from Mineral Entry and Access to Federal Land ......................................... 46
Selected Critical Minerals-Related Legislation in the 115th and 116th Congresses ....................... 47
116th Congress ......................................................................................................................... 47
115th Congress ......................................................................................................................... 48
Previous Congresses................................................................................................................ 48
Additional Policy Options ............................................................................................................. 49
Minerals Information Administration...................................................................................... 49
Greater Exploration for Critical Minerals ............................................................................... 49
Other Policy Options ............................................................................................................... 49
Additional Considerations ....................................................................................................... 50

Figures
Figure 1. Critical Minerals: Global Production (2017) ................................................................. 17
Figure 2. Critical Minerals: Global Reserves (2017) .................................................................... 25
Figure 3. Critical Minerals: Net U.S. Import Reliance (2017) ...................................................... 33

Tables
Table 1. Timeline of Selected Molycorp, Inc.,-Related Activities................................................... 4
Table 2. Critical Minerals: Global Production and Leading Producers, Selected Years................ 14
Table 3. U.S. Secondary Recovery of Critical Minerals, 2017...................................................... 19
Table 4. Critical Minerals: Global Resources and Reserves, 2017................................................ 21
Table 5. Critical Minerals: Major End Uses and Net U.S. Import Reliance .................................. 30
Table 6. Selected Materials for Wind Power ................................................................................. 37
Table 7. Selected Materials for Photovoltaic Solar Cells and Panels ............................................ 38

Appendixes
Appendix. Selected Statutes and Regulations Related to Mining on Federal Lands ..................... 51

Contacts
Author Contact Information .......................................................................................................... 51

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Introduction
President Trump and various U.S. lawmakers have expressed concerns about U.S. reliance on
critical mineral imports and the vulnerability to critical mineral disruptions of supply chains for
various end uses, including defense and electronics applications. Chinese export quotas on a type
of critical minerals referred to as rare earth elements (REEs) and China’s curtailment of rare earth
shipments to Japan over a maritime dispute in 2010 represented a wakeup call for the United
States on China’s near-monopoly control over global REE supply.1 The actions of the Chinese led
to record high prices for REEs and, as a result, began to shine a light on the potential supply risks
and supply chain vulnerability for rare earths and other raw materials and metals needed for
national defense, energy technologies, and the electronics industry, among other end uses.2 U.S.
legislators have introduced and deliberated on bills that would address the potential supply risk
and vulnerability with respect to rare earth supply and bills that would promote domestic rare
earth mine development.

1 There are 17 rare earth elements (REEs): yttrium, scandium, and 15 within the chemical group called lanthanides. The

lanthanides consist of the following: lanthanum, cerium, praseodymium, neodymium, promethium, samarium,
europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. Rare earths are
moderately abundant in the earth’s crust, some even more abundant than copper, lead, gold, and platinum. While some
are more abundant than many other minerals, most REEs are not concentrated enough to make them easily exploitable
economically. The lanthanides are often broken into two groups: light rare earth elements (LREEs)—lanthanum
through europium (atomic numbers 57-63), and the heavier rare earth elements (HREEs)—gadolinium through lutetium
(atomic numbers 64-71). Yttrium is typically classified as a heavy element.
Currently, the dominant U.S. end uses for rare earth elements are for automobile catalysts and petroleum refining
catalysts; use in phosphors in color television and flat panel displays (cell phones, portable DVDs, and laptops);
permanent magnets and rechargeable batteries for hybrid and electric vehicles; and numerous medical devices. There
also are defense applications such as jet fighter engines, missile guidance systems, antimissile defense, and satellite and
communication systems. Permanent magnets containing neodymium, gadolinium, praseodymium, dysprosium, and
terbium are used in numerous electrical and electronic components and new-generation generators for wind turbines.
2 For more information on critical mineral end uses, see Table 5.

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After 2010, decisionmakers were faced with various policy questions, including is a domestic
supply chain necessary to address potential supply risk; and would an RRE alternative supply
chain outside China among allies provide reliable and less risky access to RREs? As events
unfolded during the 2010s, it became clear that providing an upstream supply outside China was
not enough, and that access to and the reliability of entire supply chains for rare earths and other
minerals essential for the economy and national security also were vulnerable.
The concern among many in Congress has evolved from rare earths and REE supply chains, to
also include other minor minerals or metals that used in small quantities for a variety of
economically significant applications.3 These minor metals are used in relatively small amounts
in everyday applications such as laptops, cell phones and electric vehicles, and renewable energy
technologies, in addition to national defense applications. In December 2017, the Presidential
Executive Order (E.O.) 13817, “A Federal Strategy to Ensure Secure and Reliable Supplies of
Critical Minerals,” tasked the Department of the Interior (DOI) to coordinate with other executive
branch agencies to publish a list of “critical minerals.”4 DOI published a final list of 35 critical
minerals in May 2018.5

From 2010 to Present
Initially after China’s actions in 2010 contributed to prices for the various elements increasing,
the focus in Congress was on rare earth supply (e.g., where in the United States new REE
production could begin). Since 2010, several bills have been introduced that would use a variety
of policy options and approaches—from streamlining the permitting framework for rare earth
elements and other mining and processing projects on federal land, to the additions of REEs to
the National Defense Stockpile.6 Sections 1411 and 1412 of the National Defense Authorization
Act for FY2014 (P.L. 113-66) contained language for Department of Defense to begin studies of
rare earth materials and to require purchases of heavy REEs for the national defense stockpile.
In 2010 the sole U.S. rare earth mine located in Mountain Pass, CA, owned by Molycorp, Inc.,
was dormant. From the mid-1960s through the 1980s, Molycorp’s Mountain Pass mine was the
world’s dominant source of rare earth oxides. However, by 2000, nearly all of the separated rare
earth oxides were imported, primarily from China. Because of China’s REE oversupply and
lower-cost production, as well as a number of environmental (e.g., a pipeline spill carrying

3 Minor metals are primarily byproducts of base metals (e.g., copper, iron, nickel, zinc) and typically not traded on

exchanges.
4 The National Science and Technology Council Subcommittee on Critical and Strategic Mineral Supply Chains
(CSMSC) and Executive Order (E.O.) 13817 define critical minerals as those that have a supply chain that is vulnerable
to disruption, and that serve an essential function in the manufacture of a product, the absence of which would cause
significant economic or security consequence. Strategic minerals are defined as a subset of critical minerals and are
essential for national security applications. For more on E.O. 13817, see https://www.federalregister.gov/documents/
2017/12/26/2017-27899/a-federal-strategy-to-ensure-secure-and-reliable-supplies-of-critical-minerals.
5 83 Federal Register 23295, May 18, 2018. The December 2018 list of critical minerals includes: aluminum,
antimony, arsenic, barite, beryllium, bismuth, cesium, chromium, cobalt, fluorspar, gallium, germanium, graphite,
hafnium, helium, indium, lithium, magnesium compounds, manganese, niobium, platinum group metals, rare earth
elements, potash, rhenium, rubidium, scandium, strontium, tantalum, tellurium, tin, titanium, tungsten, uranium,
vanadium, and zirconium. This is not a static list and is subject to change. For more on E.O. 13817, see section on
“Development of the Critical Minerals List” in this report.
6 The National Defense Stockpile (50 U.S.C. §98 et seq.) was established in 1939 to retain stocks of strategic and
critical materials, thus, reducing dependence on foreign sources during times of national emergencies. The stockpile
was set up for national defense purposes only and not to be used as an economic stockpile.

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contaminated water) and regulatory issues at Mountain Pass, Molycorp, Inc. ceased production at
its mine in 2002.
Between 2010 and 2012, there was some optimism but also criticism over Molycorp Inc.’s
approach to reopen the only rare earth mine in the United States and establish a vertically
integrated operation including oxide separation, production of metal alloys, and permanent
magnet production.7 A few important questions relevant to a vertically integrated approach were
raised then as they are now




How can a fully integrated supply chain be developed domestically?
Is a domestic supply chain necessary to address potential supply risk?; and
With China in a near-monopoly position in all aspects of the rare earth supply
chain, would an alternative supply chain outside China among allies provide
reliable and less risky access to needed rare earth elements?

Another immediate concern focused on the investment and skill level needed to build-out a
reliable supply chain outside of China.
In 2012, Molycorp, Inc., reopened its Mountain Pass mine, and the Lynas Corporation, Ltd. began
production in Australia which added more REEs to the global mix—albeit most of the production
was in light rare earth elements (LREEs), not the heavy rare earth elements (HREEs) are needed
for permanent magnets—the fastest growing use for rare earth elements at the time. Permanent
magnets are important parts for national defense missile systems, wind turbines, and automobiles.
With higher prices came lower demand as some companies began to use less REEs, try
substitutes, or diversify their source of raw material supply outside of China. With China’s
production (including illegal production), there was more supply than demand for many of the
REEs and prices declined. As a result of rapidly falling prices and Molycorp’s debt, the Mountain
Pass mine was not economically sustainable. Molycorp filed for Chapter 11 bankruptcy
protection in June 2015. In June 2017, MP Mine Operations LLC (MPMO) purchased the
Mountain Pass mine for $20.5 million. MPMO is an American-led consortium of which the
Chinese-owned Leshan Shenghe Rare Earth Company has a 10% nonvoting minority share. In
2018, MMPO reportedly restarted production at Mountain Pass. See Table 1 for Molycorp’s
timeline. In March 2019, the Chinese government announced a reduction in REE production
quotas and suggested that the REE produced in China would be sold only in China for its
domestic manufacturing activity.8

7 Permanent magnets are important parts for national defense missile systems, wind turbines, and automobiles.
8 Tom Daly, “China Sets Lower Rare Earth Output Quotas for First Half of 2019,” Reuters, March 15, 2019,

https://www.reuters.com/article/us-china-rareearths-quotas.

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Table 1. Timeline of Selected Molycorp, Inc.,-Related Activities
Mid-1960s
through 1990s

Molycorp’s Mountain Pass mine in the 1960s-1980s was the world’s dominant source of rare
earth oxides. U.S. production began to rapidly decline in the 1990s, as China’s lower cost
production began to accelerate.

By 2000

Nearly all of the separated rare earth oxides in the United States were imported, primarily
from China.

2002

Because of China’s oversupply and lower-cost production, and a number of environmental
(e.g., a pipeline spill carrying contaminated water) and regulatory issues at Mountain Pass,
Molycorp ceased production at its mine. Since then, the United States has lost nearly all of its
capacity in the rare earth supply chain, including intellectual capacity.

2008

Under new ownership, Molycorp embarked upon a campaign to change the rare earth
position in the United States with its “mine to magnet” (vertical integration) business model.

2011

Molycorp broke ground for a new separation facility at the Mountain Pass mine to facilitate a
proprietary oxide separation process that it had designed to use fewer reagents and recycle
the wastewater, thus eliminating the need for a disposal pond.
(April) Molycorp acquired the Japanese subsidiary Santoku America in Tolleson, AZ, and
renamed it Molycorp Metals and Alloys (MMA). This acquisition was part of the firm’s
strategy to become a vertically integrated company. It produced both neodymium iron-boron
(NdFeB) and samarium cobalt (SmCo) alloys used in the production of permanent magnets.
Molycorp Metals and Alloys was the sole U.S. producer of the NdFeB alloy.
(April) Molycorp purchased a 90.023% majority interest in AS Silmet (renamed Molycorp
Silmet), an Estonian-based rare earth element and rare metals processor.
(November) Molycorp entered a joint venture with Daido Steel and Mitsubishi Corporation
of Japan to manufacture sintered permanent rare earth (NdFeB) magnets in Japan that were
sold on the world market.

2012

(June) Molycorp acquired Neo Materials Technology, Inc., a Toronto-based firm (renamed
Molycorp Canada) with rare earth processing and permanent magnet powder facilities in
China. Molycorp restarted rare earth production.

2015

(June) Molycorp files for Chapter 11 Bankruptcy Protection.

2016

(August) Neo Performance Materials is established as a private company following the
restructuring of Molycorp. Molycorp remains a separate entity as owner of Mountain Pass
Mine.

2017

Neo Performance Materials completes an initial public offering (IPO) on the Toronto Stock
Exchange.

2017

(June) A consortium, MP Mine Operations, LLC (MPMO)—comprised of JHL Capital Group,
LLC (aka MP Materials) (65%); QVT Financial LP (25%); and Leshan Shenghe Rare Earth
Company (10%)—purchase Mountain Pass Mine for $20.5 million.

2018

(January) According to MPMO, production at Mountain Pass restarted in January of 2018.
Production data were not available at the time of this writing.

Sources: CRS using CRS Report R41347, Rare Earth Elements: The Global Supply Chain, by Marc Humphries, and
articles from http://www.mining.com including “Molycorp Thrown a Lifeline” (August 31, 2016), and “Mountain
Pass Sells for $20.5 Million” (June 16, 2017), by Andrew Topf.

As previously noted, the vulnerability concerned expanded from RREs to critical minerals.
Assessments using a criticality matrix identified minerals (such as REEs, cobalt, and tantalum,
among others) that could face supply restrictions and result in vulnerabilities to the economy and
national security.9 Broad criticality assessments were prepared by the National Research Council,
9 A criticality matrix is a two-dimensional presentation of a mineral’s importance of use and availability. This

framework for analysis seeks to emphasize on a vertical axis whether minerals are easily substitutable, identify the

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the Department of Energy (DOE), and the Massachusetts Institute of Technology (MIT) early in
the recent discussion of mineral supply risk and potential mineral demand from the energy
technology sector.10 Many others, such as Nassar, Du, and Graedel,11 have weighed in since 2010
on the criticality and supply risk question, providing a variety of models that examine the supply
risk and vulnerabilities associated with these minerals. It is beyond the scope of this report to
evaluate those models.

Congressional Interest
Proposed Congressional findings mentioned in a number of bills introduced since the 111th
Congress on critical minerals include:





Emerging economies are increasing their demand for REEs as they industrialize
and modernize;
A variety of minerals are essential for economic growth and for infrastructure;
The United States has vast mineral resources but at the same time is becoming
more dependent on imports;
Mineral exploration dollars in the United States are approximately 7% of the
world total (compared to 19% in the early 90s);




Heavy rare earth elements are critical to national defense;
China has near-monopoly control over the rare earth value chain, and there has
been a transfer of technology from U.S. firms and others to China in order to gain
access to rare earths and downstream materials;




Thorium regulations are a barrier to rare earth development in the United States;
A sense of Congress that China could disrupt REE and other critical mineral
supplies to the United States;
It is important to develop the domestic industrial base for the production of
strategic and critical minerals; and
The United States must accept some risk in the form of aiding domestic
investment opportunities.




The Senate Committee on Energy and Natural Resources held a hearing on S. 1317, the American
Mineral Security Act, on May 14, 2019, “Examining the Path to Achieving Mineral Security.”12
Two congressional hearings were held on critical minerals in the 115th Congress: one on
December 12, 2017, by the House Natural Resources Subcommittee on Energy and Mineral
Resources on “Examining Consequences of America’s Dependence on Foreign Minerals,” and a

impacts of potential supply restrictions, and on the horizontal axis the potential supply risks associated with geology,
ecology, technology, economics, and the political environment. Many analysts have used the criticality matrix to rank
the criticality of selected minerals.
10 National Research Council, Minerals, Critical Minerals, and the U.S. Economy, National Academies Press, 2008;
U.S. DOE, Critical Materials Strategy, December 2011; American Physical Society and The Materials Research
Society, Energy Critical Elements, Securing Materials for Emerging Technologies, 2011.
11 N.T. Nassar, Xiaoyue Du, and T.E. Graedel, “Criticality of the Rare Earth Elements,” Journal of Industrial Ecology,
v. 19, no. 6, 2015.
12 For hearing details, see https://www.energy.senate.gov/public/index.cfm/hearings-and-business-meetings?ID=
559FE490-CA2A-4A56-9C30-F5ED5B0C7780.

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second on July 17, 2018, by the Senate Committee on Energy and Natural Resources to examine
the final list of critical minerals.13
Public resource and minerals policy options are among the options for creating reliable supply
chains of these minerals and metals. The Administration and many in Congress have combined
concerns over import dependence and developing domestic supply into a number of policy
proposals that would aim to streamline the permitting process for domestic critical mineral
production and possibly open more public lands to mineral exploration. A 2017 U.S. Geological
Survey (USGS) report, Critical Mineral Resources of the United States, presents its mineral
assessments of 23 critical minerals for the nation as a whole, but does not break out what might
be available on federal lands, where many of the legislative proposals are directed.14 Others in
Congress want to be sure that if a more efficient permitting process is put in place, all the
mechanisms for environmental protection and public input are left intact, if not enhanced.15

The Scope of This Report
This report examines the process by which the critical minerals list was drafted, why these
minerals are being classified as critical, where production is taking place, and countries holding
the largest reserves of critical minerals. There is a brief review of materials required for lithiumion batteries and solar and wind energy systems, and a discussion of supply chains for rare earth
elements and tantalum. This report also presents the statutory and regulatory framework for
domestic mineral production, legislative proposals, and congressional and executive branch
initiatives (and actions), as well as an overview of U.S. critical mineral policy.
There are a number of policy issues related to U.S. critical minerals, such as trade policy
(particularly with China) and conflict minerals,16 just to name two. Treatment of these issues is
beyond the scope of this report.

Brief History of U.S. Critical Minerals and Materials
Policy
Minerals for national security have long been a concern in the United States. For example, there
were concerns over shortages of lead for bullets during the early 1800s. There were material
shortages during WWII and the Korean War that contributed to the formation of the National
Defense Stockpile. The current stockpile of strategic and critical minerals and materials was
developed to address national emergencies related to national security and defense issues; it was
not established as an economic stockpile.

13 For hearing details, see House Natural Resources Subcommittee on Energy and Mineral Resources hearing,

https://docs.house.gov/committee/calendar/byevent.aspx?eventID=106736 (December 21, 2017); and Senate Energy
and Natural Resources hearing, https://www.energy.senate.gov/public/index.cfm/2018/7/full-committee-hearing-toexamine-the-department-of-the-interior-s-final-list-of-critical-minerals (July 17, 2018).
14 USGS, Critical Mineral Resources of the United States—Economic and Environmental Geology and Prospects for
Future Supply, Professional Paper 1802, 2017, http://doi.org/10.3133/pp1802.
15 U.S. House of Representatives, Committee on Natural Resources, H.Rept. 112-583, Report Together with Dissenting
Views on H.R. 4402: National Strategic and Critical Minerals Production Act of 2012.
16 Conflict minerals are defined as ores that when sold or traded have played key roles in helping to fuel conflict and
extensive human rights abuses in far eastern Democratic Republic of the Congo (DRC). The main conflict minerals are
tantalum, tin, tungsten, and gold (also known as “3TGs”).

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In 1939, after Germany invaded Poland, the Strategic Materials Act of 1939 (50 U.S.C. §98, P.L.
76-117) provided the authority for the United States to establish a strategic materials stockpile.
Then in 1946, the Strategic and Critical Materials Stockpiling Act was enacted so that the United
States would be prepared for national military emergencies and to prevent material shortages. The
1946 Act (P.L. 79-520) set a target of $2.1 billion of materials to be spent for the stockpile.17
Congress increased funding for supplying the stockpile to $4 billion over four years (1950-1953).
The Defense Production Act of 1950 (50 U.S.C. §4501, P.L.81-774) added $8.4 billion to expand
supplies of strategic and critical materials.18
In 1951, President Truman formed the Materials Policy Commission (also known as the Paley
Commission) which recommended a stockpile for strategic materials and the use of lower cost
foreign sources of supply. President Eisenhower established long term stockpile goals during a
national emergency as a way to prevent the shortages that occurred during World War II and the
Korean War.
The initial time frame for the duration of the emergency the stockpile was intended to cover was
three years, but later reduced to one year. However, with the passage of the 1979 Strategic and
Critical Minerals Stockpiling Revision Act (P.L. 96-41), a three-year military contingency was
reestablished as a criterion for stockpile goals. Funding for the stockpile was subsequently
increased to $20 billion.
During the Cold-War era, the National Defense Stockpile (NDS) had an inventory of large
quantities of strategic and critical materials. In the early 1990s, after the Cold War with the Soviet
Union, the U.S. Congress supported an upgrade and modernization of the strategic materials
stockpile. By FY1993, the National Defense Authorization Act (NDAA) for Fiscal Year 1993
(P.L. 102-484) authorized a major sell-off of 44 obsolete and excess materials in the stockpile
such as aluminum metal, ferrochromium, ferromanganese, cobalt, nickel, silver, tin, and zinc.19
The majority of these materials were sold to the private sector. Proceeds of these sales were
transferred to other federal or Department of Defense (DOD) programs.

The Modern Day Stockpile
In 1988, the Secretary of Defense delegated the management of the stockpile to the
Undersecretary of Defense for Acquisition, Technology, and Logistics and operational activities
of the NDS to the Director of the Defense Logistics Agency (DLA). Among other duties, the DLA
manages the day-to-day operations of the stockpile program.
The current stockpile contains 37 materials valued at $1.152 billion.20 Much of the materials are
processed metals or other downstream products such as, columbium (niobium) metal ingots,
germanium metal, tantalum metal, metal scrap, beryllium rods, quartz crystals, and titanium
metal.
Congressional action starting in 2014 led to the acquisition of REEs and other materials for the
NDS. The DLA is acquiring six materials based on the NDAA for FY2014: Ferro-niobium;
17 The stockpile consisted of many base metals and minerals such as copper, lead, zinc, aluminum, chromite, tin, and

quartz among others.
18 CRS Report 95-5, The National Defense Stockpile: A Historical Perspective, by Alfred R. Greenwood, December 14,
1994, p. 2 (out of print; available to congressional clients upon request).
19 GAO, NSIAD-93-60, p. 12. Also, see pp. 37-38 for list of proposed disposals.
20 U.S. Department of Defense, Office of the Under Secretary of Defense for Acquisition, Technology, and Logistics,
Strategic and Critical Materials Operations Report to Congress, January 2017, pp. 7-8.

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dysprosium metal; yttrium oxide; cadmium-zinc-telluride substrates; lithium-ion precursors; and
triamino-trinitrobezene.21
In FY2016, the DLA made progress on its FY2014 goals for high-purity yttrium and dysprosium
metal. The NDS initiated a program to develop economical methods to recycle REEs from scrap
and waste. The goal was to investigate technologies to determine whether recycling is feasible in
the United States.22 Work on this project goal is ongoing.
In addition to acquisitions and upgrades, Congress approved a DOD proposal to sell materials
determined to be in excess of program needs as part of the FY2017 NDAA (P.L. 114-328).

Initiatives and Actions on Critical Minerals
Development of the Critical Minerals List
E.O. 13817, “A Federal Strategy to Ensure Secure and Reliable Supplies of Critical Minerals,”
published on December 20, 2017, tasked the Department of the Interior (DOI) to coordinate with
other executive branch agencies in establishing a draft list of critical minerals published in the
Federal Register 60 days from the initial order. On December 17, 2017, the Secretary of the
Interior issued Secretarial Order (No. 3359, “Critical Mineral Independence and Security”)
directing the U.S. Geological Survey (USGS) and Bureau of Land Management (BLM) to
develop the list.23 DOI agencies, with cooperation from others (e.g., DOD, DOE, and members of
the National Science and Technology Council Subcommittee on Critical and Strategic Mineral
Supply Chains [CSMSC]), developed using specific criteria an unranked list of 35 minerals. The
Secretary of the Interior issued the final list of critical minerals in May 2018.24
The USGS used the critical mineral early warning methodology developed by the CSMSC as its
starting point for the draft list.25 One of the metrics used was the Herfindahl-Hirschman Index
which measures the concentration of production by country or company. Another metric used was
the Worldwide Governance Index, which was used to ascertain the political volatility of a country
and is based on six indicators.26 The early warning methodology is a two-stage process. The first
stage uses the geometric mean of three indicators to determine if the mineral is potentially
critical: supply risk (production concentration), production growth (change in market size and
geological resources), and market dynamics (price changes). The second stage uses the results of
the first stage to determine which of the potentially critical minerals require an in-depth analysis.
In developing the list, the USGS also relied on its net import reliance data;27 its Professional
Paper 1802, (referenced in footnote 14 of this report); NDAA FY2018 (P.L. 115-91) from DOD;
U.S. Energy Information Administration (EIA) data on uranium; and the input of several subject
21 Ibid, p. 9.
22 Ibid, p. 6.

Secretary’s Order 3359, “Critical Mineral Independence and Security” (December 21, 2017), https://www.doi.gov/
sites/doi.gov/files/uploads/so_criticalminerals.pdf.
24 83 Federal Register 23295, May 18, 2018.
25 Draft Critical Mineral List—Summary of Methodology and Background Information—U.S. Geological Survey
Technical Input Document in Response to Secretarial Order No. 3359, Open File Report 2018-102, DOI/USGS.
26 Those six indicators are accountability, political stability and absence of violence, government effectiveness,
regulatory quality, rule of law, and control of corruption.
27 “Net import reliance” refers to the percentage of a mineral commodity used by the United States that must be
imported from another country.
23

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matter experts. The USGS established a threshold above which the minerals were deemed to be
critical. Some minerals below the threshold that had critical applications were also included on
the list. The USGS used a supply chain analysis to include some metals, such as aluminum,
because the United States is 100% import reliant on bauxite, the primary source mineral for
aluminum production.
The unranked list of 35 minerals does not indicate the levels of criticality for some versus others.
This is of note because some earlier studies had shown that the supplies of platinum group metals,
REEs, niobium, and manganese are potentially far more vulnerable than lithium, titanium, and
vanadium.28 Further, the REEs are not broken out by element. Some of the heavy rare earth
elements have been shown to be more critical and vulnerable to supply shortages than some of the
lighter elements.

Other Federal Critical Minerals Actions
In addition to developing a critical minerals list, Congress and various executive branch entities
have invested in other actions related to critical minerals. Investment in research and development
(R&D) is considered by many experts (e.g., DOE, MIT, and elsewhere)29 to play a critical role in
the support for and development of new technologies that would address three primary areas:
greater efficiencies in materials use; substitutes or alternatives for critical minerals; and recycling
of critical minerals. Below is a summary of selected current federal R&D, and information and
analysis activities on critical minerals at federal agencies.

Department of Energy30
Critical Materials Hub
DOE’s FY2019 budget request included funding for R&D on rare earth and other critical
materials. DOE’s “Critical Materials Hub” is conducting R&D on a number of critical material
challenges, including “end of life” recycling to help mitigate any possible supply chain
disruptions of REEs. Funding for the program was at $25 million, each year, for the past three
fiscal years (FY2017-FY2019), as FY2019 is the third year of its second five-year research
phase.31 Congress approved this level of support despite the Trump Administration’s proposal to
eliminate the program in FY2019 and FY2020. The Critical Materials Hub is funded under the
Advanced Manufacturing R&D Consortia within DOE’s Energy Efficiency and Renewable
Energy Program.

REEs from Coal
Additionally, in FY2019 DOE proposed to launch its Critical Materials Initiative within the Fossil
Energy R&D program under the Advanced Coal Energy Systems program to examine new
technologies to recover REEs from coal and coal byproducts. Congress had appropriated funding
28 National Research Council, Minerals, Critical Minerals, and the U.S. Economy, National Academies Press, 2008.

The list is fluid; mineral with low measure of criticality today may have a higher measure of criticality in months or a
few years depending on many variables.
29 See footnote 10 of this report for reports by DOE, MIT, and the National Research Council weighing in on critical
minerals.
30 Budget information on DOE programs obtained from DOE Budget Highlights, FY2010-FY2019 Congressional
Budget Request.
31 The first phase, funded at about $125 million, ran from FY2012 to FY2016.

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for this project under the National Energy Technology Lab (NETL) R&D program during the
Obama Administration, despite no request for funding. For FY2019, the Trump Administration
requested $30 million in funding for the Critical Materials Initiative; Congress elected to support
the initiative at $18 million.

Critical Minerals Report
In December 2010 and December 2011, DOE issued Critical Materials Strategy reports. These
reports examine and provide demand forecasts for rare earths and other elements required for
numerous energy and electronic applications.32 An update on this research is forthcoming,
according to DOE.33

Department of the Interior
The National Minerals Information Center housed within the USGS provides an annual summary
of critical mineral activity in its Mineral Commodities Summaries report and Minerals
Yearbook.34 The USGS also provides mineral resource assessments and has in 2017 published a
study on 23 mineral commodities, all of which have been listed as critical by the
Administration.35 In 2010, the USGS released a report on the rare earth potential in the United
States.36 A 2017 collaboration between the USGS and the State of Alaska issued a report on
critical and precious minerals in Alaska37 and conducted a geospatial analysis identifying critical
mineral potential in Alaska.38 The results of the analysis provided new information on areas of
Alaska that might contain deposits of critical minerals.

Department of Defense
In a DOD-led assessment of the U.S. manufacturing and defense industrial base and supply chain
resiliency, there are sections on critical minerals and impacts on national security.39 The DOD
continues to fulfill its stockpile goals for various critical materials and has funded small R&D
projects related to rare earths.40
32 U.S. Department of Energy, Critical Materials Report, December 2011.
33 Personal communication with Diana Bauer, Director of Energy Systems Analysis and Integration, Office of Energy

Policy and Systems Analysis, May 16, 2019.
34 Department of the Interior, USGS, Mineral Commodity Summaries, https://minerals.usgs.gov/minerals/pubs/mcs/;
USGS, Minerals Yearbook, https://minerals.usgs.gov/minerals/pubs/myb.html.
35 U.S. Department of the Interior, USGS, Critical Mineral Resources of the United States—Economic and
Environmental Geology and Prospects for Future Supply, Professional Paper 1802, 2017.
36 U.S. Department of the Interior, USGS, The Principal Rare Earth Elements Deposits of the United States—A
Summary of Deposits and a Global Perspective. USGS Scientific Investigations Report 2010-5220.
37 U.S. Department of the Interior, USGS, Geospatial Analysis Identifies Critical Mineral-Resource Potential in
Alaska, fact sheet, March 2017.
38 USGS, Geospatial Analysis Identifies Critical Mineral-Resource Potential in Alaska, Fact Sheet 2017-3012, March
2017.
39 U.S. Department of Defense, Assessing and Strengthening the Manufacturing and Defense Industrial Base and
Supply Chain Resiliency of the United States, Report to Donald J. Trump by the Interagency Task Force in Fulfillment
of Executive Order 13806, September 2018.
40 For stockpile goals, see footnote 20 of this report. For small grant programs, see ASM International, “Army Research
Lab project to develop U.S. supply chain for rare earth elements,” June 10, 2014, http://www.asminternational.org/
home, and Texas Rare Earth Resources, “U.S. Defense Logistics Agency Awards Texas Rare Earth Resources Strategic
Materials Research Contract,” September 25, 2015, http://www.marketwired.com/press-release.

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In 2009, the Office of Industrial Policy reviewed the rare earth mineral supply chain. The Office
of the Secretary of Defense reviewed its National Defense Stockpile and issued a report titled:
Reconfiguration of the National Defense Stockpile Report to Congress.41
As part of the Ike Skelton National Defense Authorization Act for FY2011 (Section 843 of P.L.
111-383), the DOD was required by Congress to prepare an “Assessment and Plan for Critical
Rare Earth Materials in Defense Applications” and report to a number of congressional
committees by July 6, 2011.42 A DOD assessment and congressional appropriations supported
new stockpile goals for HREEs.
In an April 2012 interview with Bloomberg News, the DOD head of industrial policy stated that
DOD uses less than 5% of the rare earths used in the United States, and that DOD was closely
monitoring the rare earth materials market for any projected shortfalls or failures to meet mission
requirements.43

White House Office of Science and Technology Policy
In 2010, the White House Office of Science and Technology Policy (OSTP) formed an
Interagency Working Group on Critical and Strategic Minerals Supply Chains.44 The group’s
focus is to establish critical mineral prioritization and to serve as an early warning mechanism for
shortfalls, to establish federal R&D priorities, to review domestic and global policies related to
critical and strategic minerals (e.g., stockpiling, recycling, trade, etc.), and to ensure the
transparency of information.
The White House National Science and Technology Council Subcommittee on Critical and
Strategic Mineral Supply Chains produced a report describing a screening methodology for
assessing critical minerals.45 The “early warning screening” approach for material supply
problems was first included as a U.S. policy goal in the National Materials and Minerals Policy,
Research and Development Act of 1980 (30 U.S.C. §1601) (P.L. 96-479).46

41 Department of Defense, Reconfiguration of the National Defense Stockpile Report to Congress, April 2009.

https://www.dla.mil/Portals/104/Documents/StrategicMaterials/Reports/Operations%20Report/
FY16%20Operations%20Report_FINAL_Website%20Version.pdf.
42 Letter from the Congress of the United States, directed to The Honorable Leon E. Panetta, U.S. Department of
Defense, August 5, 2011.
43 Ratnam, Gopal, “Rare Earth Shortage Would Spur Pentagon to Action,” Bloomberg News, April 9, 2012,
http://www.bloomberg.com/news/2012-04-09/rare-earths-shortage-would-spur-pentagon-to-action.html.
44 The group’s participants include representatives from the Department of Energy, the Department of Defense, the
Department of the Interior, the Department of Commerce, the Environmental Protection Agency, the Department of
State, the Department of Justice, and the Office of the U.S. Trade Representative.
45 National Science and Technology Council, Committee on Environment Natural Resources, and Sustainability,
Subcommittee on Critical and Strategic Mineral Supply Chains, Assessment of Critical Minerals: Screening
Methodology and Initial Applications, March 2016, https://www.whitehouse.gov/sites/whitehouse.gov/files/images/
CSMSC%20Assessment%20of%20Critical%20Minerals%20Report%202016-03-16%20FINAL.pdf.
46 U.S. Governmental Accountability Office, Advanced Technologies: Strengthened Federal Approach Needed to Help
Identify and Mitigate Supply Risks for Critical Raw Materials, GAO-16-699, September 2016, p. 9.

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Supply: Critical Minerals Production and Resources
Production/Supply
According to the 2019 USGS Mineral Commodity Summaries report,47 China ranked as the
number one producer of 16 minerals and metals listed as critical. While there are no single
monopoly producers in China, as a nation China is a near-monopoly producer of yttrium (99%),
gallium (94%), magnesium metal (87%), tungsten (82%), bismuth (80%), and rare earth elements
(80%). China also produces roughly 60% or more of the world’s graphite, germanium, tellurium,
and fluorspar. In 2017, the United States had no primary production of 22 minerals and byproduct
production of five minerals on the critical minerals list. There is some U.S. primary production of
nine minerals, and the United States is a leading producer of beryllium and helium (see Table 2,
Figure 1).
China had gains in production that far outpaced the rest of the world. By 2003, China had already
dominated in the production of graphite, indium, magnesium compounds, magnesium metal,
REEs, tungsten, vanadium, and yttrium; it solidified its number one producing status of these
minerals about a decade later. Chinese producers are seeking not only to expand their production
capacity at home but to continue to negotiate long-term supply agreements or create equity
partnerships around the world, particularly in Africa (cobalt and tantalum), Australia (lithium),
and South America (lithium).48
The dominant producing region for chromium, manganese, platinum group metals, tantalum, and
cobalt is southern Africa. Brazil produces 88% of the world’s niobium, and Australia accounts for
58% of the world’s lithium production, according to USGS data. According to USGS data,
critical minerals dominated by a single producing country include: niobium from Brazil, cobalt
from the Democratic Republic of the Congo (DRC), platinum group metals from South Africa,
REEs (including yttrium), and tungsten from China.

Production of Minerals and Mineral Resource Potential on Federal Land
Current mineral production information on federal land is not available from the DOI. The
Government Accountability Office (GAO) noted in a 2008, report that the DOI does not have the
authority to collect information from mine operators on the amount of minerals produced or the
amount of mineral reserves on public lands, and there is no requirement for operators to report
production information to the federal government.49
However, previous DOI50 and GAO51 reports completed in the early 1990s reported that gold,
copper, silver, molybdenum, and lead were the five dominant minerals produced on federal lands
under the General Mining Law of 1872 (30 U.S.C. §§21-54). Currently, the vast majority of
47 USGS, Mineral Commodity Summaries 2019, February 2019, https://minerals.usgs.gov/minerals/pubs/mcs/2019/

mcs2019.pdf. The annual report used 2017 data; 2018 is estimated.
48 Elizabeth C. Economy and Michael Levi, By All Means Necessary, How China’s Resource Quest Is Changing the
World, Council of Foreign Relations, 2014; The Society for Mining, Metallurgy, and Exploration (SMME), “Annual
Mining Review,” Mining Engineering, vol. 60, no. 5, May 2018, p. 47, http://www.miningengineeringmagazine.com.
49 GAO, Hardrock Mining: Information on State Royalties and Trends in Mineral Imports and Exports, GAO-08-849R,
July 21, 2008.
50 U.S. Department of the Interior, Task Force on Mining Royalties, Economic Implications of a Royalty System for
Hardrock Minerals, August 16, 1993.
51 GAO, Mineral Resources: Value of Hardrock Minerals Extracted From and Remaining on Federal Lands,
GAO/rced-92-192, August 1992.

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mining activity on federal lands is for gold in Nevada, based on past DOI information. The DOI
report also showed that federal lands mineral production represented about 6% of the value of all
minerals produced in the United States. There is uncertainty over how much production of
minerals occur on federal lands. Most minerals listed as critical are locatable on U.S. federal
lands under the General Mining Law of 1872; comprehensive information on which minerals are
located and produced on federal land remains incomplete. An unanswered question is the extent
that critical mineral resource potential exists on federal land. Until more is known through
mineral resource assessments of federal land, it will be hard to determine the impact of opening
federal land to development that is now withdrawn from mineral development.
Some mining advocates support developing domestic supply chains in critical minerals. Other
stakeholders support a diversified portfolio of reliable suppliers, particularly if foreign sources are
more economic or if domestic production (or manufacturing) is uneconomic, not technically
feasible, or environmentally unacceptable.

Byproduct Supply
There are six critical minerals that are classified as byproducts: indium, tellurium, gallium,
germanium, cobalt, and rhenium.52 There are important differences between main product and
byproduct supply. Byproduct supply is limited by the output of the main product. For example,
the amount of indium recoverable in zinc cannot be more than the quantity of indium in the zinc
ore. As production of the main product continues, the byproduct supply may be constrained
because a higher price of the byproduct does not increase its supply in the immediate term. Even
in the long run, the amount of byproduct that can be economically extracted from the ore is
limited. That is, byproduct supply is relatively inelastic (i.e., not particularly responsive to price
increases of the byproduct). For byproducts, it is the price of the main product, not the byproduct
that stimulates efforts to increase supply. But a high enough byproduct price may encourage new
technologies that allow for greater byproduct recovery from the main product. There may be
occasions when the main product supply contains more byproduct than is needed to meet
demand. If this were the case, byproduct processing facilities would need to be expanded so that
byproduct processing capacity would not be a limiting factor in byproduct supply.
Another important difference between byproduct and main product is that only costs associated
with byproduct production affect byproduct supply. Joint costs (costs associated with production
of both products) are borne by the main product and do not influence byproduct supply.
Byproducts are typically available at lower costs then the same product produced elsewhere as a
main product, (e.g., REEs produced as a byproduct of iron ore in China would have lower
production costs than would REEs produced elsewhere in the world as a main product).
Byproducts, typically, are not free goods, meaning that there are costs associated with their
production. Byproducts could be without cost if two conditions are met: (1) production of main
product must require the separation of the byproduct, and (2) no further processing of the
byproduct is required after separation.

Global Mineral Production
Table 2 provides data on the global production of critical minerals and the leading producing
countries. The data shows that production for nearly all of the critical minerals has increased
52 A byproduct is a secondary or additional product associated with production of the main/primary ore and is limited

by the output of the main/primary product. Co-products share joint production costs as no single co-product can support
mine development costs alone.

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since 2000, many of which have doubled (e.g., chromium, indium, lithium, manganese, niobium,
and tantalum) or tripled (e.g., cobalt, gallium, and tellurium) in the amount produced.
Table 2. Critical Minerals: Global Production and Leading Producers, Selected Years
(data in metric tons (mt) or million metric tons (m mt) unless otherwise noted)
Global Production
Leading
Producers in 2017

Mineral

2000

2010

2017

Aluminum
(bauxite)

135.0 m mt

209.0 m mt

309 m mt

Australia (28.5%),
China (22.6),
Brazil (12.5%),
Guinea (15%),
Others (21.4%)

No bauxite produced
in the United States

Antimony

118,000 mt

167,000 mt

137,000 mt

China (72%),
Others (28%)

Relatively little U.S.
production; none
reported in 2017

Arsenic

33,900 mt

52,800 mt

34,600 mt

China (69%),
Others (31%)

No U.S. production

Barite

6.2 m mt

7.85 m mt

8.7 m mt

China (37%),
India (18%),
Others (45%)

No U.S. production

Beryllium

280 mt

205 mt

210 mt

U.S. (71%),
Others (29%)

U.S. is a net exporter

Bismuth

5,880 mt

8,900 mt

17,100 mt

China (73%),
Others (27%)

No U.S. production

Cesium

NA

NA

NA

NA

No U.S. production

Chromium

14.4 m mt

23.7 m mt

30.2 m mt

South Africa (46.2%),
Kazakhstan (12.9%),
Others (40.9%)

No U.S. production

Cobalt

33,300 mt

89,500 mt

120 m mt

DRC (61%),
Others (39%)

Some U.S. production
as byproduct of
copper

Fluorspar

4.5 m mt

6.0 m mt

5.7 m mt

China (61%),
Mexico (18%),
Others (21%)

No U.S. production

Gallium

100,000 kg

182,000 kg

320,000 kg

China (94%),
Others (6%)

Small amount of lowgrade gallium as a U.S.
byproduct

Germanium

71,000 kg

118,000 kg

106,000 kg

China (57%),
Others (43%)

Small amount of U.S.
production as
byproduct of zinc ore

Graphite
(Natural)

571,000 mt

925,000 mt

897,000 mt

China (75%),
Brazil (10%),
Others (15%)

No U.S. production

Hafnium

NA

NA

NA

NA

See zirconium

Helium

98 million
cubic meters
(mcm)

75 mcm

160 mcm

U.S. (57%),
Qatar (28%),
Algeria (8.7%),
Others (6.3%)

U.S. is a leading
producer

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Global Production
Leading
Producers in 2017

Mineral

2000

2010

2017

Indium

335 mt

609 mt

714 mt

China (40%),
South Korea (31.5%),
Others (27.5%)

Data is for refinery
production

Lithium

14,000 mt

28,100 mt

38,000 mt

Australia (58%),
Chile (21%),
China (9.8%),
Argentina (8.3%),
Others (2.9%)

Some U.S. production

Magnesium
Metal

368,000 mt

757,000 mt

1.1 m mt

China (89%),
Others (11%)

Some U.S. production

Manganese

7.28 m mt

13.9 m mt

17.3 m mt

South Africa (31%),
Australia (16%),
Gabon (12.7%),
China (9.8%),
Others (30.5%)

No U.S. production

Niobium

32,600 mt

62,900 mt

69,100 mt

Brazil (88%),
Others (12%)

No U.S. production

Platinum

155,000 kg

192,000 kg

199,000 kg

South Africa (72%),
Russia (11%)

The data in this row
represents platinum
only. Palladium
production of 225,000
kg is split between
two major producers
– South Africa (39%)
and Russia (38%).
Small amount of U.S.
production

Potash

25.3 m mt

33.7 m mt

41.4 m mt

Canada (29%),
Russia (17.6%),
China (13%),
Others (40.4%)

Relatively little U.S.
production (roughly
1%)

Rare Earth
Elements

83,500 mt

133,000 mt

132,000 mt

China (80%),
Australia (14%),
Others (6%)

No production in
2017. The USGS
estimates U.S.
production to be
around 15,000 mt in
2018.

Rhenium

28,400 kg

47,200 kg

51,600 kg

China (55%),
Poland (19%),
U.S. (17%),
Others (9%)

Relatively small
amount of U.S.
production as
byproduct of copper
recovery

Rubidium

NA

NA

NA

NA

No U.S. production

Scandium

NA

NA

NA

NA

No U.S. production

Strontium

520,000 mt

405,000 mt

255,000 mt

Spain (35.3%),
Mexico (28%),
China (19.6%),
Iran (15.7%)

No U.S. production

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Global Production
Leading
Producers in 2017

Mineral

2000

2010

2017

Comments

Tantalum

836 mt

681 mt

1,810 mt

DRC (42%),
Rwanda (24%),
Nigeria (8.5%),
Others (25.5%)

No U.S. production

Tellurium

125 mt

NA

470 mt

China (68%),
Japan and Russia about
12% each,
Others (9.2%)

Some U.S. production
as byproduct of
copper and lead
recovery

Tin

238,000 mt

256,000 mt

313,000 mt

China (29.7%),
Indonesia (26.5%),
Burma (15%),
Others (28.8%)

No U.S. production

Titanium

4.3 m mt

6.4 m mt

5.5 m mt

South Africa (18%),
China (15%),
Canada (16%),
Australia (13%)

Relatively small
amount of U.S.
production

Tungsten

37,400 mt

68,800 mt

82,100 mt

China (82%),
Others (18%)

No U.S. production

Uranium

NA

1,506 mt

1,021 mt

Kazakhstan (39%,
Canada (22.5%),
Australia (10%)

Some U.S. production

Vanadium

43,000 mt

57,600 mt

71,200 mt

China (56%),
Russia (25%),
South Africa (11.2%)

No U.S. production

Zirconium

1.04 m mt

1.25 m mt

1.55 m mt

Australia (32.5%),
South Africa (24.3%),
China (9%),
Others (34.2%)

Some U.S. production

Source: USGS, Mineral Commodity Summaries, 2019. Data on uranium from the Energy Information
Administration.
Notes: kg = kilograms; NA = not available. DRC = Democratic Republic of Congo; U.S. = United States.
The table is using 2017 data from the USGS Mineral Commodity Summaries, 2019 report because the report
provides actual data for 2017 and only estimated data for 2018.
Some countries may be listed as leading producers but not listed as leading reserve holders of the same mineral
listed in Table 4.

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Figure 1. Critical Minerals: Global Production (2017)

Source: Figure created by CRS based on USGS Mineral Commodity Summaries, 2019.
Notes: Color codes: Blue = North America; Purple = South America; Orange = Europe; Green = Africa &Middle
East; Red = Asia and Russia; Dark Green = Australia; and Gray = Other countries that are not specifically
mentioned in the previous columns.

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Secondary Recovery of Critical Minerals in the United States
Secondary recovery can occur from waste products during the metal refining and manufacturing
process or from discarded end use products. As indicated in Table 3, in the United States, there is
little to no production or reserves and little to no secondary recovery currently for many (but not
all) of the critical minerals of high net import reliance.
There is a significant amount of secondary recovery in the United States of nine critical minerals
according to the USGS Mineral Commodity Summaries: aluminum, chromium, cobalt, gallium,
indium, magnesium metal, platinum group metals, tin, and titanium. While U.S. capacity for
secondary recovery of metals and other materials has not grown much between 1997 and 2016,
rates of recovery have fluctuated annually. Steel is the most recycled material in the United
States. There are well established infrastructures, for old and new scrap, for selected metals such
as steel, copper, aluminum, cobalt, and chromium.53 For many other metals, such as manganese,
REEs, and niobium, little-to-no recycling takes place in the United States because it is either
economically or technically not viable.54 Countries in the European Union, Japan, and South
Korea are strengthening their efforts in secondary recovery as emerging markets (e.g., China and
India) seek to secure greater access to primary materials.
The quantity of most metal and materials available for recycling will likely continue to meet a
fraction of demand, particularly if demand is rising. The rate of availability (i.e., based on the
useful life of the product) puts a limit on how much can be recycled. According to the National
Research Council, the primary impediment facing secondary recovery in the United States is the
lack of clear policies and programs at all levels of government to embrace the recovery of
materials.55 Without a national mandate, the National Research Council report indicates that state
and local governments are likely to continue a “patchwork” of programs and policies.56
Table 3 illustrates the point that there is very little secondary recovery of critical minerals and
metals in the United States.57 The data could indicate that there is a lack of infrastructure for
secondary recovery of critical minerals and metals. Economic and technological factors must also
be evaluated as to whether the benefits outweigh the costs for recovering certain materials,
particularly the small amounts of critical minerals that may be available for secondary recovery
(from manufacturing waste or end use products). Additional R&D may be needed to determine
whether secondary recovery of the most import-dependent minerals could be increased to reduce
U.S. import reliance.
In 2018, the USGS reports that for base metals and precious metals the recycling rate is much
different. For example, the recycling rates were 28% for aluminum, 35% for copper, 52% for
nickel, 18% for silver, and 25% for zinc. In 2014, steel in the auto industry was recycled at
106%—more steel than was used for domestic manufacturing. The recycling rate of steel is 90%
for appliances containing steel and 67% for steel cans.

53 Old scrap is material in discarded or obsolete products that have reached the end of their life. New scrap is material

generated from processing primary materials. Almost all new scrap is recycled, and thus, it is not always considered a
substitute for primary material.
54 Manganese used in making steel is typically recycled as part of ferrous and nonferrous steel scrap.
55 National Research Council, Minerals, Critical Minerals, and the U.S. Economy, Washington, DC, 2008.
56 Ibid.
57 Base metals are any of the nonprecious metals. Precious metals include gold, silver, and platinum.

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Table 3. U.S. Secondary Recovery of Critical Minerals, 2017

Mineral

Secondary Recovery as % of
U.S. Apparent Consumption
(unless otherwise noted)

Aluminum

28%

Antimony

Unknown

Arsenic

None reported

Barite

None reported

Beryllium

20%-25%

Bismuth

<5%

Both old and new scrap

Cesium

Unknown

Some formate brines reprocessed

Chromium

29%

Cobalt

29%

No primary production; secondary recovery
of purchased scrap

Fluorspar

Unknown

Very little

Gallium

Unknown

No old scrap, significant new scrap
recovered

Germanium

NA

About 30% worldwide

Graphite

Unknown

Not much because of raw material
abundance

Hafnium

Negligible

Helium

NA

Very little

Indium

Significant domestic recycling
but amount not known

On a global scale, secondary production
greater than primary production

Lithium

Very little

DOE grant was awarded in 2009 for a
recycling facility. A U.S. recycling facility for
lithium-ion vehicle batteries opened in 2015.

Magnesium
metal

120,000 tons

Old and new scrap

Manganese

Negligible

Niobium

none reported

May be as high as 20% according to USGS.

Platinum

Known for
platinum only

120,000 kilograms of platinum group metals
recovered globally from old and new scrap

Potash

None

REEs

Very little

Rhenium

Some

Rubidium

None

Scandium

None

Strontium

None

Congressional Research Service

Comments

Majority of U.S. supply is from secondary
sources

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Critical Minerals and U.S. Public Policy

Mineral

Secondary Recovery as % of
U.S. Apparent Consumption
(unless otherwise noted)

Tantalum

New scrap recovered
but amount unknown

Tellurium

Very little

Tin

25%

Titanium

69,600 tons scrap metal

Tungsten

NA

Uranium

NA

Vanadium

NA

Zirconium

Some

Comments
May be as much as 10% according to USGS.

12,300 tons, mostly old scrap

Old and new scrap

Significant amount from spent chemical
process catalysts

Source: USGS Mineral Commodity Summaries, 2019.
Notes: NA = not available. Unknown = no data reported by the USGS. The table is using 2017 data from the
USGS Mineral Commodity Summaries, 2019 report because the USGS 2019 summaries provides actual data for
2017 and only estimated data for 2018.

Reserves and Resources
There is a distinction between what is described when using the terms reserves and resources in
the context of minerals. Reserves are quantities of mineral resources anticipated to be recovered
from known deposits from a given date forward. All reserve estimates involve some degree of
uncertainty. Proved reserves are the quantities of minerals estimated with reasonable certainty to
be commercially recoverable from known deposits under current economic conditions, operating
methods, and government regulations. Current economic conditions include prices and costs
prevailing at the time of the estimate. Estimates of proved reserves do not include reserves
appreciation.
Resources are concentrations in the earth’s crust of naturally occurring minerals that can
conceivably be discovered and recovered. Undiscovered technically recoverable resources are
minerals that may be produced as a consequence of natural means, or other secondary recovery
methods, but without any consideration of economic viability. They are primarily located outside
of known deposits.

U.S. Critical Mineral Reserves and Resources
Regarding reserves, the USGS lists little to no reserves in all 35 of the critical minerals except for
helium and beryllium and significant resource potential in only tungsten, lithium, vanadium,
uranium,58 and REEs. Of the 14 critical minerals listed as 100% import dependent, the USGS lists
some reserves for two: REEs and vanadium (see Table 4 and Figure 2).59
58 Uranium data obtained from the Energy Information Administration.
59 For example, note the following minerals with some reserves and or production: arsenic—small reserves; asbestos—

small reserves; bauxite—small production and reserves; fluorspar—byproduct of lime; thorium ore—some reserves, no
U.S. production; yttrium—some reserves, little production; rare earths—some production, large reserves; rubidium and

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Regarding resources, USGS identifies some resource potential for cesium, manganese, and
niobium. There are byproduct resources of cobalt, germanium, tellurium, and rhenium that are
associated with main products such as copper, zinc, and bauxite (see Table 4). The USGS is
uncertain about U.S. and global reserves of several critical minerals as not enough data are
available according to the USGS.60

Global Critical Mineral Reserves and Resources
According to the USGS, at the global level, there are significant or abundant resource potential
for the critical minerals for which the agency has data, which is some but not all of the critical
minerals. Global resource potential is either unknown or uncertain for bismuth, cesium,
germanium, indium, and tellurium. Most of the germanium, indium, and tellurium are obtained as
byproducts of base metal production.
China leads the world in reserves in seven critical minerals, including antimony, REEs, strontium,
tellurium, tin, tungsten, and vanadium (see Table 4). China is among the top three reserve holders
in barite, fluorspar, graphite, magnesium compounds, and titanium.
Table 4 provides available information on global resources of critical minerals, as well as
information on the size of the reserves. Figure 2 provides information on the regional distribution
of the reserves.
Table 4. Critical Minerals: Global Resources and Reserves, 2017
(data in metric tons unless otherwise noted)
Leading Reserve
Holders by Country

Comments

30 b mt

Guinea (24.6%), Australia
(20.6%), Vietnam (12.3%),
Brazil (8.6%), Jamaica (6.6%)

China has 3% of reserves
but produces almost
23% of bauxite.

Some resource
potential in Alaska,
Montana and Idaho.
Principal global
resources in
Australia, Bolivia,
China and Mexico

1.5 b mt

China (32%), Russia (23%),
Bolivia (21%)

The United States has
about 4% of global
reserves

Arsenic

Unknown

NA

NA

No U.S. reserves; world
reserves unavailable but
estimated at about 20x
current global
production.

Barite

2 billion tons
worldwide;
significant U.S.
resources

320 m mt

Kazakhstan (26.5%), India
(16%), China (11%), Turkey
(11%), Others (35.5%)

No U.S. reserves

Mineral

Resources

Reserves

Aluminum
(Bauxite)

Abundant global
resources; U.S.
resources not
significant

Antimony

thallium—no production, small reserves. China produces 99% of the world’s yttrium. There is no planned or current
production of bauxite or fluorspar on public lands. The USGS indicates U.S. mineral reserves of beryllium, helium,
lithium, platinum group metals, REEs, tungsten, and uranium.
60 See the USGS 1802 Study and Mineral Commodity Studies.

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Mineral

Resources

Reserves

Leading Reserve
Holders by Country

Beryllium

60% of world’s
estimated100,000
mt of resources in
the U.S.

NA

NA

Bismuth

NA

NA

NA

No U.S. reserves

Cesium

Some U.S. resource
potential, world
resources unknown

90,000 mt

Zimbabwe (67%),
Namibia (33%)

No U.S. reserves

Chromium

Small U.S.
resources
Significant world
resources

560 m mt

Kazakhstan (41%),
South Africa (35.7%),
India (17.8%),
Others (5.5%)

Cobalt

Small U.S.
resources
25 m mt terrestrial;
120 m mt seabed
nodules

6.9 b mt

DRC (49%), Australia
(17.4%), Cuba (7.2%),
Others (26.4%)

Fluorspar

500 million tons
worldwide;
significant resources
in phosphate rock
in the United States

310 m mt

Mexico (21.9%), China
(13.5%), South Africa
(13.2%), Others (51.4%)

Gallium

Significant
resources
worldwide in
bauxite and zinc but
only 10%
recovered; subeconomic
resources in the
U.S. contained in
bauxite

NA

Unknown

Germanium

Uncertain

NA

Unknown

Graphite

>800 m mt inferred
resources. Small
U.S. resources

300 m mt

Turkey (30%), China
(24.3%), Brazil (24%),
Others (21.7%)

Hafnium

NA

NA

NA

Helium

20,600 million cubic
meters in the
United States

NA

U.S., Algeria, Russia

U.S. is a world leader in
reserves with 3,900
million cubic meters

Indium

NA

NA

NA

NA

Lithium

47 m mt globally;
6.9 m mt in the
United States

14 m mt

Chile (57%), Australia
(19.3%), Argentina (14.3%)
China (7%), Others (2.4%)

Small U.S. reserves but
significant resources

Magnesium
compounds

Billions of tons
worldwide

8.5 b mt

Russia (27%), North Korea
(27%), China (11.8%),
Others (34.2%)

Congressional Research Service

Comments

No stand-alone U.S.
reserves, but significant
amounts contained in
phosphate rock

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Critical Minerals and U.S. Public Policy

Leading Reserve
Holders by Country

Mineral

Resources

Reserves

Manganese

Low grade
resources in the
United States;
78% of global
resources in South
Africa

760 m mt

South Africa (30.2%),
Ukraine (18.4%), Brazil
(14.5%), Australia (13%),
Others (23.9%)

Niobium

Resources more
than adequate
supply to meet
global demand;
Low grade
resources in the
U.S.

9.1 m mt

Brazil (80%), Canada
(17.6%), Others (2.4%)

Platinum
Group
Metals

100 million
kilograms

69,000 mt

South Africa (91%)

Some U.S. reserves.
Most of the world’s
resources are in South
Africa

Potash

7 billion tons in the
United States, 250 b
mt worldwide

NA

Canada, Belarus, Russia

USGS did not report
total world reserves

Rare Earth
Elements

Abundant but not
always in minable
concentrations;
significant resources
in the United States

120 m mt

China (37%), Brazil (18%),
Russia (15%), India (5.8%),
Australia (2.8%)

Some U.S. reserves

Rhenium

Significant U.S. and
world resources

2,400 mt

Chile (54%), United States
(16.6%), Russia (12.9%),
Others (16.5%)

Rubidium

Significant world
resources

90,000 mt

Namibia (55%),
Zimbabwe (33%),
Others (12%)

Scandium

Abundant world
resources

Strontium

About 1 billion tons

6.8 b mt

China (percent of total
unknown)

USGS did not report
reserve data for other
countries

Tantalum

Some resources in
the U.S.

>110,000 mt

Australia (70%), Brazil (30%)

Data unavailable for
other countries, even
though 80% of
production is in Africa

Tellurium

NA

31,000 mt

China (21.3%), United States
(11.3%), Others (67.4%)

Some U.S. reserves
contained in copper and
lead ores

Tin

Abundant
worldwide; some
resources in the
U.S., mostly in
Alaska

4.7 m mt

China (23.4%), Indonesia
17%), Brazil (15%), Others
(44.6%)

No U.S. reserves
reported

Congressional Research Service

Comments

Unknown

23

Critical Minerals and U.S. Public Policy

Leading Reserve
Holders by Country

Mineral

Resources

Reserves

Titanium

2 billion mt of
titanium mineral
concentrate
worldwide

880 m mt

Australia (28.4%), China
(26.1%), India 9.7%), Others
(35.8%)

Tungsten

Abundant global
resources; the
United States has
significant tungsten
resources

3.2 m mt

China (57.5%),
Others(42.5%)

Uranium

7,641,600 tons
worldwide

4.4 m mt

Australia (26%), Canada
(11%) Kazakhstan (8.2%),
Niger (7.2%), Namibia
(6.8%), Russia (6.2%)

Vanadium

63 million tons
worldwide;
significant resources
in the United States

20 m mt

China (47.5%), Russia (25%),
South Africa (17.5%),
Others (10%)

Zirconium

Substantial
zirconium
resources as part of
titanium and
phosphate rock

73 m mt

Australia (57.5%),
South Africa (19%), Others
(23.5%)

Comments
Data in this row does
not include rutile (a
related mineral). Small
amount of U.S. reserves

Small U.S. reserves

Source: USGS, Mineral Commodity Summaries, 2019. Data on uranium from the Energy Information
Administration, 2018 Domestic Uranium Production Report, May 2019.
Notes: mt = metric tons; m mt = million metric tons; kg = kilograms; b mt = billion metric tons; NA = not
available.

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Figure 2. Critical Minerals: Global Reserves (2017)

Source: Figure created by CRS based on USGS data, Mineral Commodity Summaries, 2019.
Note: Color codes: Blue = North America; Purple = South America; Orange = Europe; Green = Africa; Red =
Asia and Russia; Dark Green = Australia; and Gray = Other countries that are not specifically mentioned in the
previous columns. USGS reports Strontium reserve data only for China.

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Mineral Exploration
Exploration expenditures for minerals in the United States have been rising since 2001. The
United States has maintained about 8% of the annual exploration budget for minerals worldwide
from 1997 to 2017. In 2017, these expenditures in the United States were at 225 exploration sites
(out of 2,317 exploration sites worldwide); 41% of the U.S. sites were in Nevada, 14% in Alaska,
and 11% in Arizona.61 It can take many years for mining firms to find and bring an economic
deposit into production. Thus, it is important for the industry to keep mineral projects in the
exploration-development process.
In general, mineral exploration in the United States remains focused on a few minerals, most of
which not considered critical. Exploration activity in the western states is primarily for gold,
copper, molybdenum, silver, tungsten, and uranium. There had been some reported interest in
expanding silica sand operations in Nevada, developing a copper-cobalt-gold project in Idaho on
Forest Service land,62 and thorium production on federal lands along the Idaho/Montana border.
Globally, Canada leads with the most active exploration sites, mostly for gold and base metals
(over 500 sites), followed by Australia (about 500 sites) with investments mostly in gold, base
metals, and uranium.

Locations and Minerals Being Explored
The locations and minerals being explored can be shape how critical mineral supply chains are or
may evolve. These supply chains have relevance to various policy questions, including what is
the long-term investment strategy in the United States to develop mineral extraction and
downstream metal and manufacturing capacity; and, if the focus is on building a reliable supply
chain, what part of that supply chain makes sense to develop in the United States?
There have been recent new additions to the annual USGS mineral exploration review. Data on
lithium, niobium, rare earth elements, and tungsten are now included. Data for other minerals
such as scandium, vanadium, and yttrium have been compiled since 2014.
The big global exploration story is about lithium. In 2016, global exploration dollars for lithium,
cobalt, and gold rose significantly. The lithium exploration expenditures increased four-fold since
2015 and active exploration sites rose from 56 in 2012 to 167 sites in 2017. Lithium exploration
expenditures, for example, rose from $22 million in 2015 to $128 million in 2017 as the number
of lithium exploration companies grew from 23 in 2015 to 125 in 2017. The price of lithium rose
by more than 150% from 2007 to 2016 and sits at 83% higher than its 10-year average. The
number of cobalt sites rose by 121% since 2016.63
In the United States in 2017, gold remains in the top spot for the number of exploration sites
(47%) followed by copper (12%), then lithium with 7% of the sites. USGS noted that there is
continued interest in graphite, REEs, and tungsten in the United States, but the most notable sites
are in gold exploration. Overall, 54% of the sites actively explored in the United States are for

61 SMME, Annual Mining Review, p. 47.
62 71 Federal Register 64237, “Idaho Cobalt Project Plan of Operations, Salmon Challis National Forest, Lemhi

County, ID,” November 1, 2006, http://www.govinfo.gov/app/details/FR-2006-11-01/E6-18362.
63 SMME, Annual Mining Review, p. 35.

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gold and silver and 22% for base metals. Worldwide, gold or silver accounts for 84% of the sites
actively explored.64
The USGS reported that the United States has accounted for about 7% to 8% of overall global
exploration budget over the past 10 years (about $611 million in 2017). However, the annual
review is not exactly a country-by-country comparison because the USGS uses regions such as
Latin America and Africa to compare with individual countries such as Canada, Australia, and the
United States. The mineral exploration budget directed at U.S. mineral deposits is above that of
China (5%), Russia (4%), and many countries in Latin America.65
Latin America attracts the most exploration dollars with $2.4 billion, most of which are for gold
and silver (58%) followed by base metals at 22% of exploration expenditures. Chile has seen the
most investment in Latin America, followed by Peru. Latin America is home to 70% of the
world’s known lithium deposits, known as the “lithium triangle” consisting of Chile, Argentina,
and Bolivia. In Argentina, lithium exploration sites account for 44% of exploration expenditures
followed by gold/silver at 42%, and copper at 9%. Lithium is most developed in Chile because of
its superior infrastructure for mining. Most exploration projects in Chile are for copper (49%) and
gold (29%).66
There has been an uptick in lithium exploration in Australia as well. China invested $650 million
(in U.S. dollars) in Australia in 2016, looking for lithium and gold, primarily.67 As ore grades
decline at known reserve locations, many exploration companies are searching for high-grade
deposits in remote locations, including the ocean floor.

Demand: Critical Mineral End Uses and U.S. Import
Reliance
Demand for Critical Minerals
The demand for mineral commodities is a derived demand which differs from consumer goods
demand. Minerals are used as inputs for the production of goods and services. For example, the
demand for rare earth elements is derived from the production of their end-use products or use,
such as flat panel displays, automobiles, or catalysts. As a result, the demand for critical minerals
depends on the strength of the demand of the final products for which they are inputs. An increase
in the demand for the final product will lead to an increase in demand for critical minerals (or
their substitutes).
In the case of derived demand, when mineral and metal prices rise, the extent to which the
quantity of a material declines depends largely on the degree to which its price increase can be
passed on to the final consumer, as well as the proportion of the final good’s price that is
accounted for by the mineral/metal commodity. That is, it might depend on the amount of critical
mineral or metal used per unit of output. The major variables that determine the growth in
demand for consumer goods are price and income growth.68
64 Ibid, p. 40.
65 Ibid, p. 49.
66 Ibid, pp. 40-43.
67 Ibid, p. 50.
68 Gary A. Campbell, “Theory of Mineral Demand,” Economics of the Mineral Industries, American Institute of

Mining, Metallurgical, and Petroleum Engineering, 1985.

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U.S. and Global Demand
U.S. demand has declined for some critical minerals, and for others, demand has increased but
not as much (in relative terms) as the increase in global supply. For example, over the past 20
years consumption fell for aluminum, chromium, manganese, platinum group metals, REEs,
titanium, and tantalum, among others, and demand grew slowly for lithium, germanium, and
graphite. Only for tellurium, niobium, and indium did the United States experience rapid demand
growth (relative to supply).69 Some of the demand drivers in recent decades for critical minerals
include permanent magnets using REEs, batteries using cobalt and lithium, automobiles and
electronics using tantalum and niobium, and vanadium for steel production.
Global demand data for each of the minerals listed as critical were not available at the time of this
writing. Global demand data could shed more light on where the minerals are being used for
metal alloying, the manufacturing of component parts, and final products. Embodied metals
(those that are imported as final products) are not counted as demand.70
Many critical minerals, (e.g., manganese, tungsten, and vanadium) are used for steelmaking and
infrastructure projects, such as roads, housing, rail lines, and electric power grids. Others (e.g.,
REEs, lithium, indium, tantalum, gallium, and germanium) are used in the manufacturing of highvalue electronic products, such as laptops and batteries, renewable energy systems, and other
consumer goods, such as automobiles and appliances (see Table 5).

Demand for Critical Minerals in China
There has been a surge in demand for critical minerals in China. China’s demand for natural
resources rose to historic levels and may continue to rise over the long term, even with a slowing
economy. In the recent past, China has been the fastest growing market for niobium, and in 2010
accounted for 25% of world niobium consumption.71 Manganese consumption rose from about
2,200 metric tons (mt) in 2003 to about 9,000 mt in 2008.72 China’s demand for vanadium
paralleled that of steel demand and rose 13% annually from 2003 to 2009. In general, vanadium
demand in China is projected to double from 2010 to 2025 because of its continued use in
steelmaking (including new steel-hardening requirements) and because of the potential for
application in new battery technology used for large-scale renewable energy storage (e.g.,
vanadium-redux flow battery-VRFB).73 In 2010, China accounted for 85% of chrome ore import
demand74 and is the world’s leading producer of steel (accounting for over half the world’s
production in 2017 based on the most recent data).75 Chromium is a major production input for
stainless steel. China’s chrome imports will likely continue to increase as stainless steel demand
at the global level remains a big part of China’s high-valued exports, urbanization, and future
industrial practices.

69 USGS Mineral Commodity Summaries, Various Years, 1997–2019.
70 Embodied minerals/metals are those embedded in the end use product such as an imported laptop or automobile.
71 IAMGOLD Corporation, “Niobium 101,” March 28, 2012.
72 Shaw River Manganese Limited, “Manganese Fact Sheet,” 2010, http://www.shawriver.com.au.
73 Schauss, Steven, “A Bull Market Storm Brewing for Vanadium,” January 2, 2019, http://www.mining.com/web/bull-

market-storm-brewing-vanadium.
74 International Chromium Development Association, “Industrial Minerals,” Mining Engineering, June 2011.
75 USGS, Mineral Commodity Summaries, 2019.

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Overall, in 2017, China’s cobalt smelters accounted for 60% of global supply, and 77% of cobalt
demand in China went into batteries.76 In 2017, China accounted for about 25% of platinum
demand, primarily used in jewelry making, and 26% of palladium demand, much of which is used
in catalytic converters in automobiles.77
In order for this increasing demand scenario in China to play out, the cities would need to fill up
with enough people who are making high enough wages to support the economic growth that
China is seeking. It is uncertain whether such a high level of consumer demand will materialize.
China’s economic growth has slowed considerably in the recent past from around 10% annually
in the first decade of the 2000s, to around 6% in 2014.78 However, China’s demand for minerals
will continue to put pressure on U.S. access to reliable supplies.

U.S. Imports of Strategic and Critical Minerals
Aside from a small amount of recycling, the United States is 100% import reliant on 14 minerals
on the critical minerals list, minerals that provide critical support for the U.S. economy and
national security such as, graphite, manganese, niobium, rare earths, and tantalum, among others.
The United States is more than 75% import reliant on an additional 10 critical minerals, including
antimony, barite, bauxite, bismuth, potash, rhenium, tellurium, tin, titanium concentrate, and
uranium.
The United States has increased its mineral imports from China over the past 20 years. Although
the United States has diversified its sources for some of its material requirements since 1997, the
United States imports significant quantities of critical minerals and metals and is dependent on
China as either a primary or major provider of raw materials and several metals as of 2017 (see
Table 5 and Figure 3).
While import reliance may be a cause for concern (and high levels of import reliance potentially a
security risk), high import reliance is not necessarily the best measure, or even a good measure, of
supply risk. A more relevant measure may be the reliability of the suppliers. The supply risk for
potash or bauxite, for example, may not be the same as that for REEs or niobium due to the
multiplicity of potential sources. There are a number of factors that affect the availability of
mineral supplies that may have little to do with import reliance. A company that is the sole
supplier, or a single country as a primary source, with export restrictions, would likely constitute
supply risks. But any number of bottlenecks that might arise among both domestic and foreign
producers, such as limited electric power, skilled labor shortages, equipment shortages, labor
unrest, weather or transportation delays, and opposition on environmental policy grounds, could
also pose supply risks. Any of these above-mentioned potential supply disruptions could raise
costs or prices, and exacerbate the tightness of supplies. For other minerals, such as iron ore and
molybdenum, the United States is self-sufficient. For aluminum, uranium, potash, cesium, and
rubidium, the United States’ chief trading partner is Canada, a stable ally. Also, U.S. companies
have invested in overseas operations—for example, copper and bauxite mines—and, thus, U.S.
supply sources for some materials are diversified, of higher quality, or lower cost, and located in

76 “Global and China Cobalt Market Report, 2018-2023 Featuring 5 Chinese and 14 Global Manufacturers,” News

Provided by Research and Markets, November 9, 2018, https://www.prnewswire.com/news-releases/global-and-chinacobalt.
77 Johnson Matthey, PGM Market Report, February 2018.
78 Wright, Andrew, “This Is How China’s Economy Has Changed in the Last 10 Years,” World Economic Forum, June
22, 2016.

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countries that have extensive reserves and production capacity. Such conditions may not always
exist in the United States, even when resources are present.
Table 5. Critical Minerals: Major End Uses and Net U.S. Import Reliance
Import
Reliance
(%)

Mineral

Major
End Uses

Aluminum
(Bauxite)

transportation, packaging,
building, electrical

>75

Jamaica (46%), Brazil (25%),
Guinea (15%), Other (14%)

The data reflect the
import reliance for
bauxite, the source
mineral for
aluminum

Antimony

ceramics, glass, and
rubber products, fire
retardant

85

China (61%),
Other (39%)

Major sources are
for antimony oxide

Arsenic

lead storage batteries,
herbicides, insecticides,
military applications

100

China (91%)

Import of arsenic
metal

Barite

filler, extender, and
weighing agent in paint,
plastics and rubber

86

China (63%), India (14%),
Others (23%)

Beryllium

auto and consumer
electronics, defense
applications

17

Kazakhstan (44%), Japan
(14%), Others (42%)

Bismuth

additives for lead-free
pipe fittings

97

China (80%), Others (20%)

Cesium

photoelectric cells, and
energy conversion
devices

100

Canada

According to USGS,
Most imports are
from Canada, but
percentage from
Canada unavailable

Chromium

transportation, packaging,
building, electrical

71

South Africa (97%)

Import reliance for
chromite ore

Cobalt

super alloys, aircraft
engines, batteries,
permanent magnets

69

Norway (18%), China
(12%), Japan (12%), Others
(58%)

These imports
reflect cobalt
contained in metal,
oxides and salts

Fluorspar

used in processing
aluminum, and uranium

100

Mexico (69%), Vietnam
(10%), South Africa (8%),
Other (13%)

Gallium

integrated circuits (in
high-tech equipment),
light emitting diodes
(LEDs), solar cells

100

China (32%), UK (28%),
Germany (15%), Ukraine
(14%), Other (11%)

Germanium

fiber optics, infrared
optics, solar cells, other
solar energy applications

>50

China (58%), Belgium
(26%), Other (14%)

Graphite
(Natural)

steelmaking, refractory
applications, foundry
operations, brake linings

100

China (37%), Mexico
(29%), Canada (17%),
Other (17%)

Congressional Research Service

Major
Sources

Comments

Import reliance for
germanium metal

30

Critical Minerals and U.S. Public Policy

Mineral

Major
End Uses

Import
Reliance
(%)

Hafnium

super alloys

NA

Helium

lifting gas, lab
applications, MRI, welding

—

Indium

electrical conduction,
liquid crystal displays
(LCDs), solar cells and
photovoltaics

100

China (27%), Canada
(22%), Other (51%)

Lithium

rechargeable batteries,
ceramics, glass, chemical
compounds

>50

Argentina (51%), Chile
(44%), Others (4%)

Magnesium
Compounds

Agriculture, chemicals,
construction, and
industrial applications

51

China (57%), Canada
(22%), Others (21%)

Manganese

production of steel and
other metals

100

Gabon (74%), South Africa
(13%), Australia (8%),
Others (5%)

Niobium

steel and super alloys

100

Brazil (72%), Canada (18%),
Others (10%)

Imports of niobium
include ore and
concentrate,
niobium oxides,
ferroniobium, and
niobium metal

Platinum
Group
Metals

auto catalysts, fuel cells,
jewelry

71

South Africa (44%),
Germany (15%), UK (10%).
Others (31%)

This row
represents platinum
only. The United
States is 38%
import reliant on
palladium most of
which comes from
Russia and South
Africa

Potash

fertilizer, chemical
industry applications

92

Canada (84%)

Rare Earth
Elements

permanent magnets,
petroleum refining, glass,
lasers, steel alloys,
fluorescent lighting

100

China (80%)

Rhenium

super alloys in high
temperature turbine
engine components and
petroleum-reforming
catalysts

81

Kazakhstan (34%), Canada
(19%), South Korea (13%),
Germany (10%), Others
(24%)

Rubidium

biomedical research,
electronics, specialty
glass

100

Canada

Congressional Research Service

Major
Sources
Germany, France, UK

Comments
Percentage from
each country
unavailable
United States is a
net exporter

Percentage from
Canada unavailable

31

Critical Minerals and U.S. Public Policy

Mineral

Major
End Uses

Import
Reliance
(%)

Major
Sources

Scandium

Ceramics, electronics,
lasers, radioactive
isotopes, lighting

100

Mostly from China,
Europe, Japan, and Russia

Strontium

additive in drilling fluids
for oil and gas wells

100

Mexico (52%),
Germany (39%),
Others (9%)

Tantalum

capacitors for electronic
devices

100

Brazil (35%),
Rwanda (31%),
Australia (15%),
Others (19%)

Tellurium

photovoltaic panels, solar
cells, thermoelectric
devices

>75

Canada (66%),
China (27%), Others (7%)

Tin

Chemicals, tinplate,
solder and alloys

76

Indonesia (23%), Malaysia
(23%), Peru (22%), Bolivia
(17%), Others (15%)

Titanium
Concentrate

aerospace applications

92

South Africa (35%),
Australia (27%),
Canada (12%),
Mozambique (11%),
Others (15%)

Tungsten

cutting tools, wearresistant materials used
in construction and metal
making

>50

China (32%), Germany
(9%), Bolivia (9%),
Canada (8%), Others (42%)

Uranium

fuel for nuclear reactors

93%

Canada, Australia, Russia

Vanadium

steelmaking, aerospace
applications

100

South Africa (46%),
Russia (18%), Brazil (13%),
China (10%), Others (13%)

Zirconium

Used in ceramics,
foundry sand,
refractories, and
abrasives

—

South Africa (59%),
Australia (22%),
Senegal (14%)

Comments
Percentage from
each country
unavailable

The United States
supplied 7% of the
uranium purchased
by U.S. power
plants in 2017.

The United States is
a net exporter

Source: USGS, Mineral Commodity Summaries, 2019.
Note: > = greater than.

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Figure 3. Critical Minerals: Net U.S. Import Reliance (2017)

Source: Figure created by CRS based on USGS Minerals Commodities Summaries data, 2019.
Note: Countries listed in the bar graph represent the leading supplier of U.S. imports.

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Critical Minerals and U.S. Public Policy

Materials Analysis of Critical Minerals Content in
Finished Products and Systems
Materials analysis is a useful tool to better understand various aspects of mineral demand. For
example, such analysis can provide information on how material inputs are used in component
parts and how components are used in larger systems such as solar arrays, wind turbines, and
automobiles. Using a material analysis, an analyst can obtain information on the material
intensity of a unit of production.79 This analysis can lead to manufacturing efficiencies (i.e.,
getting the same or better performance using fewer materials) or show where and how material
substitution, if possible, could occur. Manufacturing firms could then make short-term or longterm adjustments to their production processes.80
Even with materials efficiencies, where less metal is used per unit of output, overall demand
growth and lack of short-term supply capacity often drives up mineral prices.81 For example,
households in some countries are likely to have multiple units of a variety of products such as
laptops, flat panel televisions, and cell phones, etc. And because the materials intensity (small
amounts per unit output) of critical minerals is relatively low for most end-use applications, lowcost manufactured goods may contain some high-cost materials.
The remainder of this section of the report provides information on the materials content of
lithium-ion batteries, solar energy arrays, wind technologies, and permanent magnets, with a
more detailed discussion of the material requirements for wind and solar energy systems.

Lithium-Ion Batteries
The use of lithium-ion batteries for the rapidly growing electric vehicle market is expected to
transform the material requirements for battery technology. Material analysis of lithium-ion
batteries would bring to light useful insights on materials composition, cost, technologies, and
supply chains. In the case of the lithium-ion (li-ion) battery82 for electric vehicles, what is the
material composition of the battery?83 In other words, how much cobalt, lithium, nickel, and other
materials are needed per battery, how much are the material costs for each battery, and what
percent of the total battery manufacturing cost do the materials represent? Then, further, what is
the battery cost per electric vehicles? Analysts would want to know the point at which material
price increases would warrant a shift in the use of those materials. Other useful insights in
materials analysis would be to understand the suite of battery technologies being developed, their
manufacturing capacity, and the ownership structure of the supply chain for the materials and the
batteries.

79

Material intensity is the measure of the mineral input per unit of output in energy or in units over time.

80 Short-term adjustments are adjustments to production and do not require any major capital investment; long-term

adjustments require major capital investment in equipment or facilities.
81 David Humphreys, “The Great Metals Boom: A Perspective,” Resources Policy, v. 35, 2010.
82 Helbig, et al., “Supply Risks Associated with Lithium-ion Battery Materials,” Journal of Cleaner Production,
October 12, 2017 (hereinafter referred to as Helbig 2017).
83 Material composition of a product (MCP) is a unit of measurement used to study impact of metal/minerals on
demand for traditional material. MCP measures the efficiency of converting raw materials into final end use products.
The greater the efficiency, the less demand for the material per unit of output.

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A 2017 study by a group of battery technology researchers examined the supply risks associated
with lithium-ion batteries and other battery technologies to examine the implication for a carbonreduced environment.84 The authors posed the question: What are the material requirements for
the battery? They identified features of a li-ion battery, e.g., low cost, high energy, and long life.
They examined the raw material requirements for li-ion batteries, secondary supply potential, and
supply risks associated with an exhaustible resource (e.g., mineral extraction may become
uneconomic), the structure of the industry (e.g., whether there is a cartel or a monopoly producer
involved), and a surge in demand. They used supply risk indicators discussed earlier, such as the
risk of supply reduction, the risk of a surge in demand, market concentration, political stability,
substitutability, and recyclability.
The researchers’ second step was to determine the supply risk score on the technology level, for
each of the six battery types.85 There is a lithium-cobalt oxide battery which has a high energy
density but also a high cobalt content and price. The steep country risk associated with cobalt
production in the Democratic Republic of the Congo (DRC) led researchers to look for alternative
suppliers and materials that would provide high energy density and long life with less or no
cobalt. One example would be to use a manganese-oxide battery, wherein cobalt is partially
replaced by nickel and manganese. They pointed out that there are several new battery types that
use combinations of lithium, aluminum, cobalt, iron, nickel, copper, graphite, phosphate,
titanium, and manganese. The researchers identified lithium as needed for all battery types and
graphite used for all except the lithium-iron-phosphate (LFP-LTO) type, which uses titanium
instead. They reported that with a market breakthrough (by 2035) in the use of electric vehicles
containing lithium battery technology, an annual growth rate of 7.5% is needed for lithium supply
and 3% growth rate in cobalt supply to meet electric vehicle demand.86

Solar Energy Arrays and Wind Technologies
In the case of solar arrays and wind turbine technologies, USGS Minerals Information Center
conducted a technical analysis of byproduct minerals that are contained in solar energy systems:
silver, cadmium, tellurium, indium, gallium, selenium, germanium, and four of the REEs used in
wind technologies (dysprosium (Dy), neodymium (Nd), terbium (Te), and praseodymium (Pr)),
using Clean Power Plan (CPP) and no-CPP scenarios.87 USGS concluded that regardless of the
scenario, the transition to renewables is very likely to accelerate in the coming decades and that a
number of minor metals are likely to be constrained; thus rates of production of those metals
would need to be increased to meet demand unless there are manufacturing shifts. The analysis
concluded that the supply of heavy REEs used in permanent magnets (currently used in some of
the new wind turbines) will not keep pace with demand from multiple end uses. The USGS
assumed an aggressive electric vehicle market, the increased use of the magnets in electric
vehicles, and new wind turbines’ use of permanent magnets containing REEs. There is some
84 Helbig 2017. The li-ion battery is used in consumer electronics such as cell phones, laptops, notebooks, power tools,

electric vehicles, and grid storage.
85 Battery types include LCO-C (lithium-cobalt-oxide), LMO-C (lithium manganese oxide), NCA-C (nickel cobalt
aluminum), NMC-C (lithium nickel manganese cobalt), LFP-C (lithium iron phosphate), and LFP-LTO (lithium iron
phosphate). All battery types use lithium and all except the LFP-LTO use graphite.
86 Helbig 2017 reports on the study by Marscheider-Weidemann, et al., Raw Materials for Emerging Technologies,
2016.
87 Nassar, et al., Byproduct Metal Requirements for U.S. Wind and Solar Photovoltaic Electricity Generation Up to
2040 Under Various Clean Power Plan Scenarios, Applied Energy, 183 (2016) 1209-1226, http://dx.doi.org/10.1016/
j.apenergy.2016.08.062. The Clean Power Plan was an Obama Administration rule to cut carbon dioxide emissions by
32% of 2005 levels by 2030.

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disagreement over whether significant increases in REEs for magnets that would be used in wind
energy systems will occur.88
Additionally, USGS concluded that the growth in demand for byproduct metals in solar and wind
energy systems would compete with usage in electric and hybrid vehicles, and consumer
electronics. The report asserts that a key uncertainty is net material intensity, i.e., the quantity of
the byproduct metal required per unit of installed electric generating capacity, minus the amount
of recycled material. For solar cells, net material intensity per generating capacity is dependent on
the conversion efficiency of solar cells.
Related questions are: Where are the wind turbines and solar arrays being manufactured and
which countries and firms would be impacted the most by any disruption in critical mineral
supply for these end uses?

Permanent Magnets
REEs in permanent magnets is another example of how materials analysis for end uses may
inform understanding of critical minerals vulnerability. For example, some of the pertinent
questions that might be raised with respect to permanent magnets include: How much Dy, Nd, Te,
and Pr go into a neodymium-iron-boron (NdFeB) permanent magnet and what fraction of the total
cost is each element? What are permanent magnet unit production costs and what portion of the
total costs of a wind turbine or an automobile do the permanent magnets represent? And what is
the likelihood and the economics of substitution?

Materials Review of Wind and Solar Energy Systems
Below are simplified examples of material requirements for wind and solar systems.

Materials for Wind Energy
Based on the Department of Energy Report, 20% Wind Energy by 2030, wind power installations
consist of four major parts: wind tower, rotor, electrical system, and drivetrain (e.g., generator,
gearbox, and motor).89 Most of the common large wind turbines have tower heights over 200 feet
and rotor blades as long as 150 feet. The average rated capacity of an onshore wind turbine is
between 2.5 megawatts (MW) and 3 MW.90 DOE lists the following as the most important
materials for large-scale manufacturing of wind turbines: steel, fiberglass, resins (for composites
and adhesives), core materials, permanent magnets, and copper. Some aluminum and concrete is
also required (see Table 6 below). DOE considers the raw materials for large-scale wind turbines
to generally be in ample supply. Turbine manufacturing, however, would be 100% dependent on
permanent magnet imports, primarily from China, as that country produces 75% of the world’s
permanent magnets which contain REEs (assuming certain drivetrains are used). But DOE and
other wind power analysts also identify, as a potential concern, the need for increased
manufacturing capacity for fiberglass and other components such as generators, and gear boxes.
Wind power development trends at the time of the 20% Wind Energy by 2030 study were moving
towards lighter-weight materials and high-strength composites such as glass fiber-reinforced
88 Lovins, Amory, Clean Energy and Rare Earths: Why Not to Worry, May 21, 2017, http://thebulletin.org/2017/05/

clean-energy-and-rare-earths-why-not-to-worry. The articles states that magnet-free machines can perform any function
required in electric vehicles and wind turbines and that the most effective substitute is better auto or turbine design.
89 U.S. Department of Energy, Energy Efficiency and Renewable Energy, 20% Wind Energy by 2030, Increasing Wind
Energy’s Contribution to U.S. Electricity Supply, July 2008.
90 Offshore wind farms are deploying much taller structures, with longer blades and greater MW capacity.

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plastic and carbon fiber-reinforced plastic. Increased production of fiberglass, commercial-grade
carbon fiber, and permanent magnets (containing REEs) would be necessary if the United States
were to achieve 20% wind energy by 2030.
Recent analysis indicates that the offshore wind industry could be a major driver for increasing
REE demand. There are indications that the larger turbines which are better suited for offshore
locations, which also contain REEs, may be more reliable and require less maintenance than
onshore turbines.91
Table 6. Selected Materials for Wind Power
Turbine Materials

U.S. Supply

Comments

Permanent magnet

No U.S. production, little
supply from secondary
recovery

China produces nearly 75% of the world’s
permanent magnets. Significant production
increases needed for future wind power needs.

Concrete

U.S. production

Steel

U.S. production

Aluminum

U.S. production (50% import
reliant)

Copper

U.S. production

Glass fiber-reinforced plastic

U.S. production of fiberglass

Carbon fiber-reinforced
plastic

U.S. production

Adhesives (petrochemical
based)

U.S. production

Core (petrochemical based)

U.S. production

Globally, production of commercial grade
carbon fiber is about 50 million lbs. per year.
Significant production increases needed for
future wind power needs.

Battery technology containing
the following materials
Sodium sulfur

U.S. production

Zinc-bromide

U.S. production

Vanadium-redox

No U.S. production or
reserves of vanadium

Lithium-ion

Some U.S. production of
lithium carbonate, small
reserves

Polysulfide-bromide

U.S. production

91 Fishman, Tomer, and T.E. Graedel, “Impact of the Establishment of U.S. Offshore Wind Power on Neodymium

Flows,” Nature Sustainability, vol. 2, April 2019; Dodd, Jan, “Rethinking the Use of Rare Earth Elements,”
WindPower Monthly, November 30, 2019,
https://www.windpowermonthly.com/article/1519221/rethinkingtheuseofrare-earthelements.

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Source: U.S. DOE, 20% Wind Energy by 2030 (2009) and Xcel 2007 Resource Plan, “Appendix E. Wind Storage
Research and Experiments.” Wilburn D.R., Wind Energy in the United States and Materials Required for the LandBased Wind Turbine Industry From 2010 Through 2030. Scientific Investigations Report 2011-5036.
Notes: The critical minerals that could go into the manufacturing of wind turbines include the rare earth
elements used in permanent magnets, vanadium and lithium for battery technology, and aluminum. These are
shown in bold in the table.

Materials for Solar Energy
There are two major types of photovoltaic (PV) cells: crystalline silicon cells (most widely used)
and thin film solar cells. The silicon based PV cells are combined into modules (containing about
40 cells) then mounted in an array of about 10 modules. Ethylene-vinyl acetate and glass sheets
typically frame the PV module with additional aluminum frames for added protection.92 Thin-film
solar cells use layers of ultra-thin semi-conductor materials that can serve directly in rooftop
shingles, roof tiles, and building facades. Thin-film PV cells have been noted to use cadmiumtelluride or copper-indium-gallium-diselenide (see Table 7 below). A separate category of solar
technology is concentrating solar power; these systems use mirrors to convert the sun’s energy
into heat and then into electricity.
Table 7. Selected Materials for Photovoltaic Solar Cells and Panels
Solar Energy Materials

U.S. Supply

Major Import Sources

Glass

Large sand production and reserves for
making glass

Net exporter in 2008

Aluminum

U.S. supply

Net exporter in 2008

Copper

U.S. supply (32% import reliant)

Chile and Canada

Indium

Negligible U.S. supply from secondary
sources

China, Japan, and Canada

Gallium

Negligible U.S. supply as byproduct of
bauxite production

China, Ukraine and Germany

Tellurium

Byproduct of zinc production

Belgium, Canada, and China

Selenium

Byproduct of copper production

Belgium and Canada

Cadmium

Byproduct of copper production

Net exporter in 2008

Silicon Metal

Some U.S. production (less than 50%
import reliant)

Brazil, South Africa, and Canada

Source: U.S. DOE, Solar America Initiative; “Emissions from Photovoltaic Cycles,” Environmental Science and
Technology, v. 2, no. 6, 2008.
Notes: The critical minerals that could go into the manufacturing of solar cells and panels include aluminum,
indium, gallium, and tellurium: these are shown in bold.

Selected Supply Chain Analysis
With a supply chain analysis, it is just as important to know where new downstream capacity
(processing, refining, and metals alloying) is being built or likely to be built in the world as it is to
know the likely investors in upstream production capacity for critical minerals.
92 Vasilis M. Fthenakis, Hyung Chul Kim, and Erik Alsema, “Emissions from Photovoltaic Life Cycles,” Environment

Science and Technology, vol. 42, no. 6, 2008.

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When looking at the complete supply picture it could be more easily determined where the
potential risks are and what mitigation efforts may be available. Below, two illustrative supply
chains are described: rare earth elements and tantalum.

Rare Earth Elements
REE Supply
Rare earth elements often occur with other elements, such as copper, gold, uranium, phosphates,
and iron, and have often been produced as a byproduct. The lighter elements, such as lanthanum,
cerium, praseodymium, and neodymium, are more abundant and concentrated and usually make
up about 80%-99% of a total deposit. The heavier elements—gadolinium through lutetium and
yttrium—are scarcer but very “desirable,” according to USGS commodity analysts.93
Most REEs throughout the world are located in deposits of the minerals bastnaesite94 and
monazite.95 Bastnaesite deposits in the United States and China account for the largest
concentrations of REEs, while monazite deposits in Australia, South Africa, China, Brazil,
Malaysia, and India account for the second-largest concentrations of REEs. Bastnaesite occurs as
a primary mineral, while monazite is found in primary deposits of other ores and typically
recovered as a byproduct. Over 90% of the world’s economically recoverable rare earth elements
are found in primary mineral deposits (e.g., in bastnaesite ores).96

REE Supply Chain
The supply chain for rare earth elements generally consists of mining, separation, refining,
alloying, and manufacturing (devices and component parts). A major issue for REE development
in the United States is the lack of refining, alloying, and fabricating capacity that could process
any rare earth production.
An April 2010 GAO report illustrates the lack of U.S. presence in the REE global supply chain at
each of the five stages of mining, separation, refining oxides into metal, fabrication of alloys, and
the manufacturing of magnets and other components. According to the 2010 GAO report, China
produced about 95% of

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/crs%3AR45810. Public record. Not legal advice.
