The outstanding assays that just came out of American Tungsten & Antimony’s (ASX: AT4) flagship Antimony Canyon Project (ACP) in the US have hit extraordinarily high grades up to 66.47% Sb, and intersected geology extremely similar to China’s most prolific antimony district, right as antimony consumption has exploded in the US – with record prices proving no barrier to demand. Assays of 11.03m at 3.1% Sb from 25.91m including 2.62m at 12.54% Sb from 29.2m, and 8.47m at 2.67% Sb from 31.15m including 2.2m at 9.69% Sb from 36.88m, have drastically increased the potential size of the current 6.1-6.9 Mt at 1.4-2.3% Sb exploration target. These assays represent true thickness above 90%, which is far thicker than the 30cm widths typical of western antimony veins and well into the territory of the 1-5m stratiform horizons seen at Xikuangshan Antimony District, which contains the Twinkling Star Mine that holds a 400kt resource and annual production capacity of 30kt. The drilling also revealed key factors that allow the type of mineralisation at ACP to be considered analogous with Xikuangshan, such as the holes being strategically drilled east of the historically producing open-pit and successfully intersecting a flat-lying ore body that is laterally continuous, as well as stibnite mineralisation being hosted in a calcareous tuff horizon.
Determining if ACP possesses a similar magnitude of scale to that of Twinkling Star will require further work, but the aforementioned factors combined with AT4 now definitively identifying a multi-stage hydrothermal mineralising system that has deposited antimony across numerous prospects throughout ACP, is extremely encouraging. The immense scale narrative is certainly furthered when considering the similar geophysics seen 10km to the North at Dry Wash Canyon.
The results from last year’s CSAMT survey proved to be a powerful source of geophysical data, with AT4 shifting its focus midway through the drilling campaign to target the North-East aligned conductors that lit up on imaging far more than the initially interpreted North-West trending structural corridors. Alongside CSAMT, IP and EM geophysics will also form a crucial technique for identifying sulphidation and ultimately antimony mineralisation, because of the widespread replacement of host rocks by sulphide minerals such as stibnite, pyrite and marcasite observed in drill cores. Sulphide rich zones typically produce strong geophysical signals, and this has now been confirmed at ACP.
Antimony consumption in the US increased 57% to 45kt in 2025 despite prices averaging 150% higher at US$55,000/t accounting for 41% of global production the same year – which decreased 7.5% 110kt. Current prices are still tremendously strong at US$48,000/t, and both the energy transition and rise of AI are creating explosive levels of demand through antimony’s vital efficiency functions in photovoltaic solar panels and flame-retardant PVC piping in data centres – both uses of which do not have cost effective, mature substitutes.
At a market cap of $146 million with a cash balance of $12.7 million, an enterprise value of $133.3 million doesn’t price in enough of the upside that could come from near-term production at any of AT4’s critical minerals projects. The company has also been extremely active with its tungsten portfolio, having recently acquired a fully permitted 146ktpa processing mill which has capacity to expand to 310kpta and last operated in 2017, to accompany its Dutch Mountain project. The tenement package contains numerous past-producing mines such as the Fraction Lode Mine, which produced 275t of skarn and vein-hosted scheelite at an estimated head grade of 1.7% WO₃, and the Е. H. В. Lode claim, which historically produced 2,374t averaging 1.3% WO₃. These are astoundingly high grades by all standards, and are also up to 10 times higher than the 0.17% WO₃ resource recently published of at United States Antimony Corp’s (UAMY) Canadian project.
This whole operation in Utah is in addition to its tungsten portfolio in Nevada, which includes a 780kt resource grading between 0.3%-0.5% WO₃ at Tennessee Mountain, as well as the Nightingale Tungsten District, which has previously been mined at grades up to 1.0% WO₃ and recorded historical production of 564,000 pounds of 70% WO₃ concentrate. AT4 has just added to Nightingale with the Sage Hen Tungsten Project, which has historic production grades of 1.0% WO₃ and massive skarn bodies at depth that will soon be explored. Our last tungsten article on AT4 in November covered these projects and can be read here. At the time, tungsten prices more than doubled in price from US$320/mtu at the start of 2025 to US$705/mtu, but have since risen to an astounding US$2,400/mtu in under 4 months – as the industry faces a catastrophic breakdown in supply while demand growth shows little signs of backing off.
AT4 is also still swiftly moving towards its pilot mining campaign later in the year, and a recent highly successful metallurgical testwork program also saw the production of the first antimony ingots from ore at ACP, which served as a proof of concept that supports the Metso Ausmelt concept study and plant design delivered in September – which can be operational in under two years.
Every single one of the initial seven drill holes from this campaign at ACP were mineralised, with four of them containing significant amounts of antimony mineralisation. AT4 targeted the Emma and Gem mines during this campaign because they were the highest grade production centres in the district, and they sit on patented claims. The tuff unit, which has a ‘Salt & Pepper’ appearance, is the main host for high-grade stibnite and outcrops extensively on these private claims – making for the highest priority drill targets. The Emma Prospect also produced at an average grade of 1.5% Sb, with a high grade zone averaging 2.2% Sb. There are 3 holes set to be drilled at the Gem prospect, where assays up to 17.94% have been recorded and an underground development has been driven into the south canyon wall along a sub-horizontal mineralised zone, demonstrating both the continuity and accessibility of high-grade mineralisation.
A cross section of Little Emma can be seen below, showing the drill holes intersecting the flat-lying orebody that is an extension of previous mining activity, along with the locations of high-grade samples:
Source: AT4
The geological setting of Xikuangshan can be seen below, illustrating its stibnite orebodies that are concentrated within favourable Upper Devonian carbonate-rich stratigraphy, and are also closely associated with major faults, fracture zones and silicified alteration corridors, highlighting the same combination of host-rock control and structural fluid pathways that ACP possesses:
Source: AT4
Below is a photo of the first antimony ingots from Antimony Canyon, which AT4 had made at an independent third-party metallurgical facility:
Source: AT4
China suspended its export ban for antimony in November last year, which has actually created a very functional narrowing of the gap between Chinese and international antimony prices, as domestic supply from inside China has resumed sales into the global market. The Western world has continued to establish key infrastructure for critical mineral production, and Trafigura recently shipped its first batch of antimony from the newly revamped Port Pirie facility in SA. This operation stems from a $135 million funding package that was assembled from the Australian Federal Government, as well as the South Australian and Tasmanian state governments, which was aimed at modernising two domestic smelting operations.
The rise of antimony use in photovoltaics still has serious potential to inflict severe distress on the antimony market, and has been significantly quelled in recent times with regulatory measures that can only last for so long. The 2021 groundbreaking research on antimony’s added efficiencies to photovoltaics saw rapid uptake by the solar panel industry, which accounted for 16kt of consumption that year – a figure that $28 billion financial services giant China Merchant Securities is forecasting will rise to 68kt in 2026.
This extreme level of demand has also been echoed by Twinkling Star Chairman Kang Dongsheng, who was a prime beneficiary of this new industry trend during China’s antimony export ban – with the mine having no trouble selling its metal domestically. This structural demand setting is the perfect environment for AT4 to launch more extensive exploration plans across its massive Antimony Canyon Project, as it continues to identify the easily accessible and highest grade zones to begin pilot mining later in the year.
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Disclaimer: This article is for informational and marketing purposes only, and does not constitute financial advice or a recommendation to invest. All opinions expressed are our own. We may receive fees or other forms of compensation in connection with the publication of this content, and may own shares in any of the mentioned companies. Please do your own research and seek professional advice before making any investment decisions.