Antimony: The Overlooked Critical Mineral Powering a New US–Australia Alliance
From ammunition to energy storage, antimony’s strategic importance is a key driver of capital flows and diplomacy and putting Australian small caps squarely on Washington’s radar.
What Is Antimony — and Why it Matters
Antimony (Sb) is a silvery metalloid most commonly extracted from stibnite (Sb₂S₃).
While it rarely attracts the spotlight, its applications sit at the intersection of defence, energy, and industrial resilience:
- Flame retardants – Essential in plastics, textiles, and electronics.
- Defence manufacturing – Used in alloys for bullets, batteries, and explosives.
- Advanced technologies – Found in semiconductors, sensors, and grid-scale batteries.
It’s little wonder that the US Geological Survey classifies antimony as a critical mineral vital to national security.
Few substitutes exist for its performance in munitions and high-temperature electronics, making supply security a strategic priority.
“Antimony is one of those metals nobody talks about, until you can’t get it.”
Mining industry executive, Critical Minerals Forum 2025
China’s Tight Grip on Supply
China continues to wield outsized control over global critical mineral supply chains, with particularly sharp influence in rare earths, antimony, gallium, germanium, and other strategic metals.
As of 2024, China produced ~60 % of global antimony output.
China’s dominance is not just in mining: it also controls much of the downstream refining, smelting, and value-add processing capacity.
But that dominance is under strain, as environmental controls, resource depletion, and stricter regulatory oversight are causing a decline in domestic antimony output.
According to a recent export-market forecast, after China tightened controls beginning December 2024, its antimony export volume and export value are expected to fall markedly in 2025 versus 2023–24 levels.
Indeed, customs data show that in June 2025, China’s exports of antimony fell ~88 % compared to January levels.
Some analysts argue China has effectively suspended most antimony exports in recent months, citing crackdowns on smuggling, trans-shipment, and a broader export licensing regime.
Export Controls, Rare Earth Leveraging & Strategic Chokepoints
Beijing’s approach to resource control has matured into a more granular “export licensing control list” model rather than blanket bans, with an emphasis on dual-use technologies, downstream processing, and sensitive end-uses.
In April 2025, new export restrictions were imposed on seven rare earth elements and magnets, requiring licensing and limiting trade in defence-sensitive sectors.
Beyond rare earths, China has also expanded controls on germanium, gallium, and antimony via addition to export control lists.
For antimony specifically, starting September 15, 2024, China formalized export controls on antimony ores, metals, oxide, and smelting/separation technology, mandating export licenses.
The Chinese Ministry of Commerce’s announcement elevated antimony to strategic status, citing its indispensability in military, aerospace, flame-retardant, and other high-tech uses.
Beyond licensing, there is heightened scrutiny and enforcement: China has cracked down on smuggling and transshipment routes (e.g. via Thailand, Mexico) used to circumvent export controls.
Interestingly, while antimony exports are collapsing, China has simultaneously revived some rare earth magnet shipments to the US, as diplomatic accords eased rare earth licensing constraints, indicating that Beijing may use rare earth exports as a diplomatic lever while more tightly controlling antimony.
Strategic Vulnerability: US Dependence & Supply Risk
The US currently imports essentially all its antimony supply, with no significant domestic production since the closure of its last major mine (Sunshine Mine, Idaho).
Chinese export controls increase the risk of sudden supply disruptions, whether for political leverage or to protect domestic security interests.
With global demand rising (defence, electronics, energy), the combination of declining Chinese output and tighter export controls creates a potent squeeze on downstream users.
Geopolitics & the New Critical Minerals Policy
Washington’s response has been swift and multipronged:
- Direct US government funding for domestic producers under the Defense Production Act.
- Public-private partnerships to rebuild industrial capacity.
- Strategic diplomacy with allied suppliers, notably Australia and Canada.
The latest symbol of this convergence between capital and policy is JPMorgan’s US$1.5 trillion “Security and Resiliency Initiative”, announced this week.
The program channels investment into critical minerals, defence, energy resilience, and frontier technologies.
Chief executive officer Jamie Dimon called it “a direct response to America’s over-reliance on unreliable sources of critical minerals.”
This alignment of Wall Street, Washington, and the Pentagon is unprecedented, and Australian miners are emerging as key beneficiaries.
Kevin Rudd and the Australia–US Strategic Push
Australia’s Ambassador to the US, Dr Kevin Rudd, has been instrumental in positioning Australian miners as trusted suppliers to America’s industrial revival.
According to ASX announcements by Nova Minerals and Resolution Minerals, Ambassador Rudd requested both companies brief him ahead of Prime Minister Anthony Albanese’s meeting with President Donald Trump on 20 October 2025, a summit expected to feature critical minerals cooperation as a major agenda item.
Rudd’s team reportedly compiled a list of Australian-listed companies with US critical-mineral assets, with a particular emphasis on antimony, to be presented at the meeting.
Building the US–Australia Antimony Corridor
Nova Minerals (ASX: NVA | NASDAQ: NVA | FRA: QM3)
- Flagship asset: Estelle Gold and Critical Minerals Project, Alaska (514 km², Tintina Gold Belt).
- Focus: Gold + Antimony across 20 prospects.
- Government support: Received US $43.4 million from the US Department of War under the Defence Production Act to establish a fully domestic antimony supply chain
- Infrastructure: Land secured at Port MacKenzie for an antimony refinery to produce trisulfide, trioxide, and refined metal for military and industrial use.
- Goal: Deliver “military-spec antimony” by 2026/27, placing Nova among the first integrated antimony producers on US soil.
“Being invited to brief the Australian Government for this high-level meeting… is a testament to the strategic importance of the Estelle Project.”
Christopher Gerteisen—chief executive officer, Nova Minerals
Resolution Minerals (ASX: RML | OTCQB: RLMLF)
- Project: Horse Heaven Gold-Antimony-Tungsten Project, Idaho (US).
- Scale: 729 federal lode claims (14,580 acres), adjacent to Perpetua Resources’ Stibnite Mine, historically responsible for 90 % of US antimony output during WWII
- Resources: Gold, antimony, and tungsten — all listed on the US Critical Minerals List.
- Status: Phase 1 drilling completed; further exploration underway.
- Strategic importance: Part of Ambassador Rudd’s US briefing list, underscoring Australia’s pivotal role in America’s mineral-security ambitions.
Other Australian Small Caps with Antimony Exposure
Project / Focus: Hillgrove Antimony–Gold Project (NSW)
Highlights: Advanced to FID; historic producer; grades > 4 % Sb
Project / Focus: Antinomy Canyon Project (Utah); Central Idaho Antimony Project (Idaho); Tennessee Mountain Tungsten Project (Nevada)
Highlights: High-grade stibnite; rebranding to American Antimony & Tungsten
Project / Focus: Halls Peak (NSW)
Highlights: Adjacent to LRV; antimony-rich polymetallic veins
Project / Focus: Multi-asset portfolio
Highlights: Broader critical-minerals exposure
Kalamazoo Resources (ASX: KZR), Warriedar Resources (ASX: WA8), Locksley Resources (ASX: LKY), Southern Cross Gold (ASX: SX2), and Marquee Resources (ASX: MQR) all have early-stage projects and / or are reviewing critical-mineral prospects.
The Capital Market Tailwind
The intersection of policy and capital is defining this next phase of mining investment:
- Government equity and grant funding (e.g., Nova’s US$43.4m DoW award).
- Private-sector capital alignment (JPMorgan’s US$1.5T initiative).
- Diplomatic coordination (Kevin Rudd’s October briefing to President Trump).
Collectively, these measures aim to de-risk critical-mineral development in friendly jurisdictions and provide small-cap leverage to a multi-trillion-dollar geopolitical race.
Outlook: The Quiet Metal Making Global Noise
Antimony’s resurgence underscores a profound shift: critical minerals are no longer just commodities; they’re instruments of statecraft.
For investors, the opportunity lies in early-stage exposure to Australian explorers building US-linked supply chains.
As the Albanese–Trump meeting approaches, antimony may soon trade not just on commodity markets, but on the world stage.
Once overlooked, antimony now stands as a test case for how allied nations rebuild industrial self-sufficiency, one small-cap at a time.
Sidebar: “Antimony by the Numbers”
Symbol / Atomic Number: Sb / 51
Major producers: China (~50 %), Russia, Tajikistan, Bolivia
Top consumers: US, Japan, EU
Main uses: Flame retardants (~50 %), batteries, defence alloys
US import reliance: ~100 %
Price trend (2020–2025): +65% (supply tightening)
Key Australian ASX plays: NVA, RML, LRV, TMG, CRR