A private lithium explorer says it has discovered what could be the largest tungsten resource in the United States, but the project’s development faces uncertainty due to concerns over its location.
According to the Financial Times, 3 Proton Lithium (3PL) has outlined a resource containing nearly 1.8 million tonnes of tungsten at its Railroad Valley Minerals project in eastern Nevada. If confirmed, it would be by far the largest known tungsten deposit in the country.
The discovery comes as tungsten demand continues to grow, driven by the aerospace and defence sectors. The metal has also become a strategic priority for the US as China, the world’s dominant producer, tightened export controls, sending tungsten prices up sixfold since early 2025.
The US has not mined tungsten for more than a decade and remains heavily reliant on imports, much of which previously came from China.
The Trump administration has moved to strengthen domestic supplies of critical minerals, with the Railroad Valley project included in the federal FAST-41 program, which aims to accelerate permitting for nationally significant infrastructure projects.
However, the project faces opposition from NASA.
The agency says about one-third of the mining claims lie within a radio quiet zone used to receive signals from satellites. NASA argues that mining activity could interfere with its operations and in 2023 urged the Bureau of Land Management to withdraw the 44 km² area from new mining activity for 20 years, according to the Financial Times.
3PL has reportedly asked the Trump administration to overturn the proposed withdrawal, arguing the project would strengthen US economic and national security by providing a domestic source of tungsten.
The outcome could determine whether one of the country’s largest potential critical mineral discoveries can move from exploration to development.
Write to Jackson Chen at Mining.com.au
Image: Great Basin, Nevada, by Ken Lund, Wikimedia Commons, under licence CC BY-SA 2.0.
