The Minerals That Define
the Next Supply Chain

Rare Earth Elements

Rare earth elements — a group of 17 metals including neodymium, dysprosium, praseodymium, and terbium — are foundational to U.S. defense systems. Permanent magnets made from rare earth alloys power the electric motors in F-35 fighter jets, Virginia-class submarines, Tomahawk missiles, and precision-guided munitions. Every advanced weapons platform in the U.S. inventory has rare earth dependencies. There is no viable substitute at scale.

The DoD has designated rare earth elements as the highest-priority category within its critical minerals program, and Title III Defense Production Act authorities have been explicitly invoked to fund domestic and allied-nation rare earth processing capacity.

China controls approximately 85–90% of global rare earth processing and separation capacity, and roughly 60% of mining output. Even deposits located outside China are largely processed through Chinese facilities — meaning supply chain vulnerability exists at the processing stage even when the ore originates in an allied nation.

The concentration is not accidental. China has invested strategically in rare earth dominance for decades, acquiring processing technology, subsidizing production, and exercising export controls at critical moments. The 2010 rare earth export restriction to Japan — which caused prices to spike by 2,000% — demonstrated exactly how this leverage operates.

U.S. government programs are actively funding rare earth mining and processing capacity in Australia, Canada, and select Indo-Pacific and African nations with known deposits. The strategic objective is to establish end-to-end supply chains — from mine to separated oxide to magnet alloy — that do not pass through Chinese processing facilities.

Projects in allied nations that can demonstrate mine-to-processing integration, or that can partner with U.S. technology transfer programs to build separation capacity, are the highest-priority targets for DoD OSC, DFC, and EXIM program investment.

RMI evaluates rare earth projects against the full spectrum of federal program eligibility — from Title III production agreements through DFC project finance and EXIM sovereign lending. Given the processing dependency problem, we specifically assess whether a project can be structured to include a U.S. government-backed technology transfer component that builds in-country separation capacity. Projects that solve the processing problem command significantly higher program interest and better offtake economics than raw ore exporters.

Tungsten

Tungsten has the highest melting point of any metal — 3,422°C — making it irreplaceable in applications requiring extreme heat resistance and hardness. It is the primary material in kinetic energy penetrators (armor-piercing ammunition), shaped charge liners, radiation shielding for nuclear applications, and high-temperature aerospace components. The U.S. military consumes tungsten across ground combat systems, naval munitions, and aerospace platforms.

The DoD has identified tungsten as a defense-critical mineral under the National Defense Authorization Act, and the lack of domestic U.S. tungsten mining — the last U.S. tungsten mine closed in 2015 — makes allied-nation sourcing an operational necessity rather than a policy preference.

China produces approximately 80% of the world's tungsten and controls the dominant share of global processing. The remaining supply comes primarily from Vietnam, Russia, and Bolivia — with Russia now sanctions-constrained and Bolivia presenting sovereign risk considerations that limit program eligibility.

This leaves a narrow set of allied-nation alternatives: select deposits in Canada, Australia, Portugal, and parts of Sub-Saharan Africa represent the primary non-Chinese, non-sanctioned tungsten supply base available to U.S. government programs.

The absence of domestic U.S. production means the Pentagon is entirely import-dependent for tungsten. U.S. government programs have been directed to prioritize tungsten supply chain development in allied nations as a matter of munitions production security — particularly given elevated consumption rates driven by current geopolitical conflicts and the drawdown of U.S. stockpiles.

Tungsten projects in eligible jurisdictions can access DoD OSC loan guarantees and Title III production agreements, as well as DFC project finance for development-stage assets. RMI's program mapping process identifies which federal vehicles apply based on the project's development stage, jurisdiction, and existing infrastructure. Given the munitions application profile, we position tungsten projects explicitly within the defense industrial base supply chain framing that program offices respond to most directly.

Manganese

Manganese is essential to steel production — no high-strength steel can be made without it — and is a critical component of lithium-manganese-oxide and lithium-manganese-iron-phosphate battery chemistries used in military electric vehicles and energy storage systems. It also plays a role in aluminum alloy production for aerospace applications.

The United States produces virtually no manganese domestically. Every ton consumed by U.S. steel mills, battery manufacturers, and defense contractors is imported.

South Africa and Gabon together account for approximately 65% of global manganese ore production. China dominates processing, converting raw ore into the electrolytic manganese metal and manganese sulfate used in battery manufacturing. Australia has significant reserves and is an allied-nation producer, but processing remains largely China-dependent across the supply chain.

The battery application for manganese has elevated its strategic profile significantly as the DoD pursues electrification of ground vehicle fleets and forward operating base energy systems. U.S. government programs are increasingly targeting manganese supply chains that can supply both the steel and battery sectors — projects that can serve dual-use demand profiles command broader program interest.

Manganese projects with dual-use profiles — serving both metallurgical and battery-grade demand — are structured by RMI to access both DoD and DFC program vehicles. The battery-grade manganese pathway connects to DoE processing technology programs as well, creating potential for multi-program engagement structures. RMI assesses the full program landscape based on the project's ore chemistry, processing capability, and end-market positioning.

Chromium

Chromium is the essential alloying element in stainless steel and superalloys used in jet engines, gas turbines, and naval vessel components. Without chromium, the corrosion-resistant, high-temperature alloys that power U.S. fighter aircraft and naval propulsion systems cannot be produced. It is also used in hard chrome plating for hydraulic systems and landing gear across military aviation platforms.

The U.S. has no domestic chromium mining. All ferrochrome — the processed form used in steel and superalloy production — is imported.

South Africa holds approximately 75% of the world's known chromite reserves and is the dominant global producer. Kazakhstan is the second largest producer. China is the dominant processor of ferrochrome, though South African producers have developed significant in-country processing capacity. Russian chromium, previously a secondary supply source, is now sanctions-constrained.

South Africa's status as both the dominant reserve holder and a relatively stable supplier makes it the primary allied-nation chromium source for U.S. government programs. However, the political risk profile and infrastructure constraints in South African mining regions require project-level risk mitigation structures — exactly the kind of DFC political risk insurance and project finance tools that RMI navigates.

Chromium projects are evaluated primarily against DFC project finance and political risk insurance vehicles, with EXIM sovereign lending applicable where government-to-government frameworks exist. RMI's approach in chromium-producing jurisdictions emphasizes the sovereign partnership development work — building the bilateral relationships that create the enabling conditions for federal program engagement before capital structures are advanced.

Lithium

Lithium is the foundational element of the battery technologies powering the U.S. military's electrification agenda — from soldier-portable power systems and unmanned aerial vehicles to electric ground vehicles and forward operating base energy storage. It is also critical to the commercial electric vehicle supply chain that underpins domestic industrial capacity.

The DoD has identified lithium battery supply chains as a critical vulnerability, and multiple federal programs have been directed to secure allied-nation lithium supply as part of the broader battery material security mandate.

The "lithium triangle" of Chile, Argentina, and Bolivia holds over 50% of known global lithium reserves. Australia is the largest lithium mine producer by volume. China dominates lithium processing and refining — converting spodumene concentrate and lithium brine into the battery-grade lithium carbonate and lithium hydroxide that cell manufacturers require. Even Australian lithium is largely shipped to China for processing.

The processing dependency mirrors the rare earth problem — allied-nation ore is feeding Chinese processing capacity, which then supplies global battery manufacturers including U.S. defense contractors. U.S. government programs are funding allied-nation lithium processing capacity to break this dependency, with DoE technology transfer programs playing a central role alongside DFC and EXIM capital vehicles.

Lithium projects are among the most multi-program eligible assets in RMI's portfolio — touching DoD, DFC, EXIM, DoE, and DoI program vehicles simultaneously. RMI structures lithium engagements to maximize program participation across the full capital stack, with particular attention to the processing technology transfer opportunity that can significantly increase a project's program value and offtake economics.

Critical Minerals

Beyond the five named mineral categories, the U.S. government's critical minerals mandate extends across a broader basket of commodities where supply chain vulnerability, defense application concentration, and allied-nation sourcing urgency align. RMI works across this broader landscape — including cobalt, graphite, nickel, vanadium, gallium, and germanium — where federal program interest is active and project-level engagement is warranted.

• Cobalt — Essential to lithium-ion battery cathodes and superalloy production for jet engines. The Democratic Republic of Congo produces over 70% of global supply, creating both sovereign risk and human rights due diligence requirements that complicate U.S. government program participation. Allied-nation alternatives in Australia, Canada, and the Philippines are priority targets.
• Graphite — The dominant anode material in lithium-ion batteries. China controls over 90% of global natural graphite processing and synthetic graphite production. There is no battery supply chain without graphite, and there is currently no scaled non-Chinese graphite processing outside of nascent capacity in Canada and Tanzania.
• Nickel — Used in battery cathodes (nickel-manganese-cobalt chemistries) and in stainless steel and superalloy production for defense platforms. Indonesia is the dominant producer but processing is largely Chinese-controlled. Australia, Canada, and select African nations offer allied-nation alternatives.
• Vanadium — Used in vanadium redox flow batteries for grid-scale energy storage and as a steel-strengthening additive in armor plating and structural defense applications. South Africa and Russia are the dominant producers, with Russia now sanctions-constrained.
• Gallium & Germanium — Semiconductor materials essential to radar systems, electronic warfare platforms, night vision equipment, and communications infrastructure. China produces over 80% of global gallium and 60% of global germanium, and has already demonstrated willingness to use export controls as a geopolitical instrument.

For projects in these mineral categories, RMI conducts the same program mapping and eligibility assessment process applied to the five named sectors — evaluating the project against current federal program parameters, identifying the applicable capital vehicles, and structuring the engagement strategy accordingly. The broader basket minerals are increasingly attracting dedicated program attention as the U.S. government expands its critical mineral investment mandate beyond the initial priority list.