What Happened to Mountain Pass Rare Earth Mine and Processing Facility?
The Mountain Pass Mine, located in California's Mojave Desert, is the only active rare earth mining and processing facility in the United States. Discovered in 1949, it dominated global rare earth production for decades before declining due to environmental issues and Chinese competition. Under current owner MP Materials, the mine has been revived and is undergoing significant vertical integration to establish a domestic mine-to-magnet supply chain, including partnerships with the U.S. Department of Defense and Apple, with operations expanding into heavy rare earth separation and magnet manufacturing as of 2026.
Quick Answer
The Mountain Pass Mine, now operated by MP Materials, is the sole rare earth mining and processing facility in the United States. After periods of closure and bankruptcy, MP Materials acquired the mine in 2017 and has since focused on restoring and expanding its capabilities to create a fully integrated domestic rare earth supply chain. As of August 2026, the company is actively commissioning heavy rare earth separation circuits at Mountain Pass, producing NdPr oxides, and developing magnet manufacturing facilities in Texas, supported by strategic partnerships with the U.S. government and major corporations.
📊Key Facts
📅Complete Timeline13 events
Discovery of Rare Earth Deposits
Prospectors searching for uranium accidentally discovered significant rare earth element deposits at Mountain Pass, California.
Molybdenum Corporation of America Begins Production
Small-scale rare earth mining operations commenced under the Molybdenum Corporation of America (later Molycorp).
Global Dominance in Rare Earth Production
Fueled by demand for europium in color televisions, Mountain Pass became the world's leading supplier, producing up to 70% of global rare earth supply.
Separation Plant Closure Due to Environmental Issues
The mine's separation plant ceased production following environmental concerns and toxic waste spills from its wastewater pipeline.
Mine Closure Amid Competition and Environmental Fallout
The entire Mountain Pass mine closed due to a combination of environmental issues and increasing competition from Chinese rare earth suppliers.
Molycorp Acquires Mine and Plans Revival
Molycorp Minerals LLC acquired the Mountain Pass mine from Chevron with ambitious plans to revive U.S. rare earth production through 'Project Phoenix'.
Molycorp Files for Bankruptcy
Despite significant investment, Molycorp filed for Chapter 11 bankruptcy due to technical challenges, cost overruns, and a collapse in rare earth prices.
MP Materials Acquires Mountain Pass
MP Mine Operations LLC (later MP Materials) acquired the mine out of bankruptcy, aiming to restart and rebuild America's rare earth industry.
MP Materials Goes Public on NYSE
MP Materials Corp. completed its SPAC merger and began trading on the New York Stock Exchange under the ticker 'MP', securing capital for expansion.
Cessation of Concentrate Sales to China and Key Partnerships
MP Materials stopped selling rare earth concentrate to China and announced major partnerships with Apple ($500M for recycled magnets) and the U.S. Department of Defense (DoD) for the 10X magnetics facility.
Q4 2025 Results and 10X Facility Site Selection
MP Materials reported record NdPr oxide production in 2025, produced its first NdFeB magnets on commercial equipment at Independence, and selected Northlake, Texas, as the site for its 10X magnet manufacturing campus.
Q1 2026 Results and Groundbreaking on 10X Facility
MP Materials announced record Q1 2026 NdPr production of 917 metric tons and broke ground on the 10X magnetics facility, with heavy rare earth separation commissioning activities at Mountain Pass set to begin imminently.
Q2 2026 Results and Aerospace/Defense Contract
MP Materials reported Q2 2026 revenue of $108.5 million, with NdPr production of 840 metric tons. The company also announced a long-term supply agreement for separated gadolinium with an unnamed U.S. aerospace and defense customer. Heavy rare earth separation circuit commissioning is in full swing.
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🔍Deep Dive Analysis
The Mountain Pass Rare Earth Mine, situated in California's Mojave Desert, holds a unique and critical position in the global rare earth supply chain. Discovered in 1949 by prospectors searching for uranium, the site quickly revealed significant deposits of bastnäsite, a rare earth-bearing mineral. Molybdenum Corporation of America (later Molycorp) acquired the claims in 1950, initiating small-scale production in 1952. The mine's output dramatically increased in the 1960s, driven by demand for europium in color television screens, leading Mountain Pass to supply up to 70% of the world's rare earths until the early 1980s.
However, this dominance began to wane in the late 20th century. Environmental concerns, particularly related to a 14-mile wastewater pipeline that experienced numerous spills of radioactive waste between 1984 and 1998, led to lawsuits and fines. Coupled with increasing competition from lower-cost Chinese suppliers, the mine's separation plant ceased production in 1998, and the entire mining operation closed in 2002. Molycorp attempted a revival after acquiring the mine from Chevron in 2008, investing over $1.5 billion in 'Project Phoenix' to modernize operations. Mining restarted in 2012, but technical challenges, cost overruns, and a collapse in rare earth prices led Molycorp to file for Chapter 11 bankruptcy in 2015.
The mine's fortunes shifted again in July 2017 when MP Mine Operations LLC, a consortium including U.S. hedge funds JHL Capital Group and QVT Financial LP, acquired Mountain Pass out of bankruptcy for $20.5 million. Rebranded as MP Materials, the company resumed mining and refining operations in January 2018, aiming to re-establish a domestic rare earth supply chain. MP Materials went public on the New York Stock Exchange on November 18, 2020, through a SPAC merger. By 2024, Mountain Pass produced over 45,000 metric tons of rare earth oxide (REO) in concentrate, accounting for about 15% of global production.
A key strategic pivot occurred in July 2025, when MP Materials ceased all sales of rare earth concentrate to China, which had previously processed most of its output. This move coincided with significant partnerships, including a $500 million agreement with Apple for recycled rare-earth magnets and a transformative public-private partnership with the U.S. Department of Defense (DoD). The DoD partnership, which includes a $150 million loan and a 15% equity stake, supports MP Materials' vertical integration strategy, particularly the construction of the '10X Facility' in Northlake, Texas, for neodymium-iron-boron (NdFeB) magnet production, expected to add 10,000 metric tons per year capacity by 2028.
As of August 2026, MP Materials continues to advance its vertical integration. The company reported Q2 2026 revenue of $108.5 million, driven by a 127% increase in separated NdPr sales volumes. NdPr oxide production reached 840 metric tons in Q2 2026, with a year-end target run-rate of 6,075 tons. Heavy rare earth (HREE) separation circuits for dysprosium and terbium are actively being commissioned at Mountain Pass, with product shipments anticipated later in 2026. Furthermore, in July 2026, MP Materials secured a long-term agreement to supply separated gadolinium oxide to an unnamed U.S. aerospace and defense manufacturer, further solidifying its role in national security supply chains. The company broke ground on its 10X magnetics facility in Q1 2026 and produced its first NdFeB magnets on commercial equipment at its Independence facility in 2025, aiming for a full mine-to-magnet domestic supply chain.
What If...?
Explore alternate histories. What if Mountain Pass Rare Earth Mine and Processing Facility made different choices?