Mountain Pass Rare Earth Mine
Mountain Pass mine – open pit (left) mill (right background) | |
| Location | |
|---|---|
| Location | Mountain Pass, San Bernardino County |
| State | California |
| Country | United States |
| Coordinates | 35°28′43″N 115°31′57″W / 35.47861°N 115.53250°W |
| Production | |
| Products | Rare-earth elements in concentrates |
| Production | 38,000 tonnes |
| Financial year | 2020 |
| Type | open-pit |
| History | |
| Discovered | 1949 |
| Opened | 1952 |
| Active | 1952–2002, 2007–2015, 2017– |
| Owner | |
| Company | MP Materials Corp. |
| Website | Mountain Pass Mine |
| Year of acquisition | 2017 |
The Mountain Pass Rare Earth Mine and Processing Facility, owned by MP Materials, is an open-pit mine of rare-earth elements on the south flank of the Clark Mountain Range in California, 53 miles (85 km) southwest of Las Vegas, Nevada. In 2020 the mine supplied 15.8% of the world's rare-earth production. It is the only rare-earth mining and processing facility in the United States. It is the largest single known deposit of such minerals.
As of 2022, work was ongoing to restore processing capabilities for domestic light rare-earth elements (LREEs) and work has been funded by the United States Department of Defense to restore processing capabilities for heavy rare-earth metals (HREEs) to alleviate supply chain risk. The mine was reported as operating in 2025.