A recent report by Nikkei News highlighted South Korea's resumption of tungsten mining, raising hopes for future supplies to Japan. At first glance, this appears to be a major boon for Japan's tungsten supply chain; however, a closer look at the respective tungsten industry chains of both nations reveals a more complex picture.
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South Korea resumed operations at the Sangdong tungsten mine in March of this year. This mine is pivotal to the country's tungsten resources; South Korea's tungsten deposits are highly concentrated in Sangdong, a site that once accounted for approximately 90% of the nation's total tungsten output. Beyond Sangdong, South Korea lacks other large-scale, economically viable tungsten deposits, and its overall exploration potential is limited. The country's total tungsten reserves stand at roughly 155,000 tonnes, representing about 3.6% of the global total.
Between 1952 and 1992, the Sangdong mine was a cornerstone of the South Korean economy; at its peak, it contributed more than half of the nation's export revenue. However, in the 1990s, a global tungsten oversupply combined with the influx of low-priced tungsten products from China forced the mine to shut down. It was subsequently acquired by Almonty Industries (a Canadian company) in 2015 and officially resumed production on March 17, 2026.
In terms of deposit type, Sangdong is a skarn-type scheelite deposit, with scheelite (CaWO₄) as the primary tungsten-bearing mineral. Currently, the mine has a production capacity of approximately 2,300 tonnes of tungsten concentrate per year, with a future target of 4,600 tonnes following capacity upgrades.
The issue, however, is that resuming mining operations is not synonymous with mastering the entire tungsten industry chain.
Transforming tungsten from raw ore into feedstock for cemented carbide involves a complex series of processes:
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In other words, mining is merely the starting point; the truly critical factor is the subsequent capacity to produce APT-ammonium paratungstate. This is precisely where South Korea faces its biggest challenge: while mining has restarted, the capacity for APT refining has essentially not been restored.
Historically, South Korea certainly possessed tungsten refining capabilities. During the mine's previous operational era, the country maintained the necessary smelting and processing infrastructure. However, following the mine's closure, the associated production lines, technical processes, and skilled workforce dissipated. More importantly, China subsequently leveraged its massive production capacity and cost advantages to gradually squeeze South Korea's original tungsten refining industry out of the market. Put simply, it is not that South Korea lacked the know-how; rather, after more than thirty years of inactivity, the industrial supply chain had been severed.
If South Korea wishes to restore its APT refining capabilities now, it faces at least three major hurdles.
First is the issue of technology and industrial experience. Large-scale hydrometallurgy is far more complex than simply preparing a batch of samples in a laboratory; it entails stable processing, equipment commissioning, environmental treatment, quality control, and continuous production. Re-establishing such operations after a hiatus of over thirty years is no easy task.
Second is the issue of economies of scale. APT refining requires significant investment yet yields thin profit margins; economic viability generally requires production at the scale of several thousand tons. South Korea's domestic demand is limited, and even with future expansion, the Sangdong mine's annual output of tungsten concentrate would only reach approximately 4,600 tons. Relying on this single mine makes it difficult to sustain a cost-competitive APT refining system.
Third is the issue of equipment and supply chains. Key equipment, mature processes, and engineering expertise within the APT supply chain are primarily held by Chinese and European companies. Consequently, rebuilding the industry with complete autonomy would be extremely challenging for South Korea.
Taking the Sangdong scheelite mine as an example: supporting an APT production capacity of around 5,000 tons requires a supply of at least 7,600 tons of tungsten concentrate. Clearly, the mine's own output is insufficient. Therefore, in the foreseeable short term, South Korea's tungsten concentrate will likely still need to be shipped to locations such as the United States for refining before undergoing further downstream processing.
This explains why Almonty plans to construct tungsten oxide refining facilities between 2027 and 2028, aligning with the restrictions on Chinese tungsten mandated by the U.S. 2027 National Defense Authorization Act (NDAA). The significance of the Sangdong mine lies primarily in supporting the U.S. strategy to reconstruct a "non-Chinese tungsten supply chain." In other words, the tungsten output from this mine is likely intended to satisfy the needs of the U.S. defense industry first, rather than those of Japan.
Now, let us consider Japan.
Following China's implementation of export controls on certain tungsten-related products, Japan is not entirely devoid of APT capabilities. The Akita plant of Japan New Metals is the country's sole APT producer; it primarily recovers tungsten from cemented carbide scrap using hydrometallurgy, with a nominal capacity of approximately 2,500 tons of tungsten equivalent per year. However, a critical issue remains: the Akita plant does not rely solely on domestic scrap to produce APT. A significant portion of its output capacity depends on the further processing of externally sourced intermediate products, such as APT and tungsten oxide. The effective capacity derived from actual domestic tungsten scrap recycling is only around 1,000 tons (tungsten equivalent).
In contrast, Japan's demand far exceeds this figure. For instance, in 2024, Japan's annual tungsten consumption stood at approximately 9,370 tons. Even after accounting for the domestic recycling capacity of roughly 1,000 tons and supplementing supplies with intermediate products from third countries, Japan still faces a substantial supply gap. This reality aligns with the widely cited figures indicating that Japan's industrial tungsten sector relies on China for over 80% of its supply, with that figure approaching 90% for semiconductor-grade high-purity tungsten.
Therefore, even if South Korea resumes mining operations at the Sangdong tungsten mine-and theoretically supplies some raw tungsten ore to Japan in the future-it is unlikely to fundamentally alter Japan's vulnerability regarding its tungsten supply chain. The core of Japan's problem is not merely a lack of ore, but the absence of a stable, comprehensive, and cost-effective tungsten supply chain.
Moreover, given the backdrop of the U.S. prioritizing the restructuring of its own defense-related tungsten supply chain, it remains highly questionable how much of the Sangdong mine's future output would actually be allocated to Japan.
