Modern economies increasingly rely on a variety of nonrenewable resources that may have supply constraints or restrictions. The nature of supply restrictions and how these supply restrictions may be alleviated can be identified to help understand and to compensate for supply constraints. Critical minerals are minerals that have been identified as being more likely to have supply constraints. McCullough and Nassar (2017) developed a methodology and studied the early warning screening of minerals for potential criticality. Specifically, they selected a list of potential indicators that could contribute to criticality, developed computational methods, and calculated criticality for a wide variety of minerals. Consequently, they identified supply risk, production growth, and market dynamics as indicators that a particular mineral is potentially critical. An updated methodology was developed and described by Nassar and Fortier (2021). In February 2022, the U.S. Geological Survey (USGS) published a revised list of critical minerals for the United States that replaced the 2018 list (Department of the Interior, 2018) and increased the number of critical minerals from 35 to 50 (U.S. Geological Survey, 2022).

Tungsten is on both the 2018 and 2022 critical minerals lists. According to Shedd (2024), 82.7 percent of all mined tungsten in the world was produced by mines in China, followed by production by mines in Vietnam (5.0 percent) and Russia (2.5 percent) (table 1).

The concentration of production in a single source country is the main reason for a high supply risk, so to reduce the level of criticality for tungsten, the concentration of production could be changed either by increasing existing production in other countries or by developing new production in other countries (Nassar and others, 2020). Alleviating the criticality of tungsten by increasing production in other countries or developing new production in other countries depends on the availability of high-quality tungsten resources that may be profitably produced elsewhere in the world.

Uzbekistan has significant resources of critical minerals, including tungsten. Eight mineral deposits—Gussay, Ingichke, Kara-Tyube, Koytash-Ugat, Lyangar, Sarykul, Sautbay, and Yakhton—are known to have significant tungsten resources (Gosudarstvennyi Komitet Respubliki Uzbekistan po geologii i mineral’nym resursam, undated a, b, c; Safirova, 2023). Some of these deposits, such as Ingichke and Koytash-Ugat, produced ore between the 1940s and 1990s. In the mid-1990s, production at these operations was stopped because low tungsten prices rendered production unprofitable. Several other tungsten deposits were considered for development in the past two decades, but as of 2023, Uzbekistan had no operating tungsten mines (Gosudarstvennyi Komitet Respubliki Uzbekistan po geologii i mineral’nym resursam, undated a, b, c; Safirova, 2023).

We analyzed three tungsten deposits in Uzbekistan (Koytash-Ugat, Yakhton, and Sautbay; fig. 1) that were identified as suitable for development (soon after discovery, preliminary feasibility studies concluded that production is likely to be profitable; Gosudarstvennyi Komitet Respubliki Uzbekistan po geologii i mineral’nym resursam, undated a, b, c) but have not yet been developed. Using a methodology that combines the geologic data from the deposits with published summary financial data from tungsten mines in other countries, we simulate potential financial outcomes and conduct sensitivity analyses with respect to uncertain price and cost parameters. We also analyzed the potential effect that development of the three mineral deposits in Uzbekistan could have on world tungsten production, and whether development of these deposits could affect tungsten criticality.

Feasibility studies contain well-researched production plans and assumptions that are presented to funders and investors, yet the projected results from these studies may differ from the actual figures realized during project implementation. Suárez Sánchez and others (2015) analyzed five new tungsten mining projects based on their published feasibility studies. The projects were Barruecopardo (Spain), Kilba (Australia), Hemerdon (United Kingdom), Sangdong (South Korea), and King Island Scheelite (Australia). Suárez Sánchez and others (2015) collected information on the projects’ capital and operating costs, planned mining and processing capacities, resources and reserves, and planned financial outcomes, such as net present values, internal rates of return, and capital payback periods (table 2). The unit of measurement for tungsten concentrates in international markets is the metric ton unit (mtu). An mtu is 1% of a metric ton, which is equivalent to 10 kg or, equivalently, 1 metric ton unit of tungsten trioxide contains 7.93 kilograms [kg] of tungsten.

For this report, we compared geologic parameters of Uzbekistan’s tungsten deposits, such as resources, reserves, and grades, with similar parameters for the deposits described in Suárez Sánchez and others (2015) and were able to estimate capital and operating costs for three hypothetical tungsten mine projects in Uzbekistan. The Hemerdon project was notable because the operating company was planning to produce tungsten and tin simultaneously, and the revenue for the tin concentrate served as a credit that reduced the operating costs of tungsten production (Suárez Sánchez and others, 2015). In the case of the tungsten deposits considered in this report, gold is a coproduct that serves a role similar to that of the role of tin in the Hemerdon project.

A synthetic modeling approach was used to obtain the data needed to produce basic results of simulated feasibility studies for three selected tungsten deposits in Uzbekistan. Geologic data for the three tungsten deposits were obtained from the Ministry of Mining Industry and Geology of Uzbekistan, and are based on information from geologic exploration studies undertaken between the 1980s and the 2000s (Gosudarstvennyi Komitet Respubliki Uzbekistan po geologii i mineral’nym resursam, undated a, b, c). Mining production parameters were obtained from published feasibility studies for more current but unrelated projects (Suárez Sánchez and others, 2015). As in actual feasibility studies, the two major results are the net present value of the project (NPV), and the number of years needed to recoup the capital investment (payback). NVP was calculated using the equationNPV=∑t=0nCFt1+rtwhere

NPV and the number of years needed to recoup the capital investment were calculated for a central scenario of the simulated feasibility study. For each production year t, CF_t is calculated as the difference between the revenue (computed as the product of the expected output price and projected production quantity) and operating costs incurred in that year. Capital costs are assumed to be incurred before the start of production, in year 0.

For the simulations, key parameters were derived from data for the five tungsten projects outlined in table 2 (Suárez Sánchez and others, 2015) and 2024 market conditions. The discount rate for all simulations is assumed to be 8 percent, as in the majority of the five tungsten feasibility studies in table 2. The central estimate price of tungsten trioxide (WO₃) per mtu of WO₃ content is assumed to be $300 per mtu, which describes the market price as of January 2024 (Almonty Industries Inc., 2024). Prices used in the feasibility studies that Suárez Sánchez and others (2015) analyzed are somewhat higher, likely because of different price expectations in the middle of the 2010s. The history of tungsten trioxide prices shows high volatility, which makes investment in tungsten projects risky. For example, from 2001 to 2023, tungsten prices have ranged from a low of $49 per mtu to a high of $358 per mtu (fig. 2; Shedd, 2002, 2006, 2010, 2014, 2018, 2023, 2024).

Geological data from the deposits were provided by the Ministry of Mining Industry and Geology of Uzbekistan (Gosudarstvennyi Komitet Respubliki Uzbekistan po geologii i mineral’nym resursam, undated a, b, c). The unpublished documents were provided by Yelena Golovko on August 24, 2022. We combined these geological data for the Koytash-Ugat, Sautbay, and Yakhton deposits and the synthetic economic assumptions based on the feasibility studies described in Suárez Sánchez and others, 2015, to create potential development scenarios for these deposits. In our simulations, gold prices appear to be a significant driver for the viability of the three tungsten projects in Uzbekistan. Uzbekistan ranks among the world leaders in gold production and has significant expertise in mining and processing gold ores (Safirova, 2023). In 2023, the price of gold was $1,900 per troy ounce (Sheaffer, 2024), but for all three projects, we used a conservative assumption for the price of gold ($50,000 per kg or $1,555 per troy ounce), and assumed that only 50 percent of gold content is recovered. We did not include other coproduct minerals mentioned in deposit descriptions, such as bismuth, copper, and silver, in our simplified simulations because they would not make a difference to the broad feasibility considerations.

Sensitivity analyses explored key uncertain parameters, such as the price of the main output (WO₃ content), the unit operating cost of production, and the total capital cost investment required to implement the project. The results of the sensitivity analysis for each hypothetical project show the variability of the simulated outcomes of the mining projects as a function of assumptions about price and cost parameters. For each sensitivity analysis, two potential changes were considered. The first was an increase (or decrease) of the total capital costs of the project by 20 percent from the central estimate and the other was an increase (or decrease) of the tungsten output price by 20 percent. In this simple model, changes in unit operating costs are mirror images of changes in output prices and are not considered separately.

The hypothetical scenarios considered in this study suggest that, if developed, the Koytash-Ugat, the Yakhton, and the Sautbay mineral deposits in Uzbekistan could produce a total of about 36,600 t of tungsten trioxide over the lifetime of the respective mines. If in operation simultaneously, the three mines could produce about 2,163 t per year of tungsten, which would constitute about 2.6 percent of the annual world production making Uzbekistan the third-ranked producer of tungsten in the world (table 13). In addition, new tungsten production in Uzbekistan could contribute to the reduction of tungsten criticality by decreasing the production concentration of tungsten.

The methodology developed for determining whether a specific mineral should be considered as critical evaluates three essential components of risk—disruption potential, trade exposure, and economic vulnerability (Nassar and others, 2020; Nassar and Fortier, 2021). In the USGS critical mineral model, which was used to produce the critical mineral list of 2022 (U.S. Geological Survey, 2022), trade exposure and economic vulnerability reflect U.S. import reliance and U.S. manufacturers’ ability to withstand hardship related to supply disruption, and are outside of the scope of this study.

Disruption potential is computed as a linear combination of the elements of the Herfindahl-Hirschman Index (HHI), and it is weighted to indicate country-specific willingness and ability to supply specific commodities. An unweighted HHI is used to assess industry concentration—in particular, it is commonly used by the U.S. Department of Justice to evaluate the effect of horizontal mergers and acquisitions (U.S. Department of Justice and the Federal Trade Commission, 2023). The unweighted HHI is calculated as the sum of squared market shares (measured as a percentage) of market participants. Low concentration of an industry is associated with an unweighted HHI below 1,500; moderate concentration of an industry is associated with an HHI between 1,500 and 2,500; and an HHI above 2,500 is considered to be a sign of a highly concentrated industry. In the case of a complete monopoly, a single supplier capturing 100 percent of the market results in an HHI of 10,000 (U.S. Department of Justice and the Federal Trade Commission, 2023, p. 5–6).

Based on the 2022 world tungsten production data (table 1), the unweighted HHI is 6,890 and reflects China’s dominance in tungsten production. Under the hypothetical scenario described in this paper, where three tungsten deposits in Uzbekistan are developed and produce 2,163 tons per year of tungsten, the unweighted HHI would decrease to 6,539, or by 351 points. Although world tungsten mining would still remain highly concentrated, development of the three deposits in Uzbekistan could reduce the degree of tungsten industry concentration and reduce its disruption potential.

One way to decrease the level of criticality for a critical mineral is to diversify where that mineral is mined. An obstacle to decreasing the level of criticality for a critical mineral is the availability of quality mineral resources that are economical to produce. In this report, we examined data from three tungsten deposits in Uzbekistan and considered whether these deposits could be developed in the near future (in the next 3 to 5 years). Using synthetic simulation analyses, we have shown that under certain assumptions, these tungsten deposits may be successfully developed and could increase world production of tungsten by 2.7 percent.

There are several important caveats with this study. Because of the nature of these analyses, the rate of uncertainty of the parameters is relatively high. In addition, the results appear to depend on the price of tungsten, which can be volatile, and on the coproduction of other high-value mineral resources, such as gold, that may make marginally economic projects more robust. More publicly accessible feasibility studies could make the modeling of the development of mineral resources, including critical minerals, more transparent for researchers, investors, and the public. The current study focuses on the mining stage only and assumes that the product at this stage is the tungsten trioxide concentrate. Complete evaluation of tungsten production would entail considerations such as whether the mined tungsten product is sent to another country for further processing and how the cost and logistics of the metallurgical processing would affect the profitability of the complete production process.