The southern Appalachian region of the eastern United States contains an estimated 1.43 million metric tons of undiscovered, economically recoverable lithium oxide — enough to replace 201 years of US imports at last year's level, according to new research published by the U.S. Geological Survey in the journal Natural Resources Research.
The lithium is concentrated in the Carolinas and is present in pegmatites, large-grained rocks similar to granite. The USGS figures represent the 50% confidence level, meaning there is an equal chance the region contains more or less than that amount. At 90% confidence, the deposit holds at least 60,000 metric tons, while a 10% probability exists that as much as 6.9 million metric tons remain undiscovered in the southern Appalachians alone. A companion study estimated a further 900,000 metric tons of lithium oxide in the northern Appalachians.
The estimated quantity could supply batteries for 80 million electric vehicles, 1 million grid-scale batteries large enough to stabilize an electric grid, 110 billion laptops — equivalent to a 600-year supply for the world at 2025 levels — or 300 billion cellphones, equating to 36 per person on earth.
The United States currently has one sole domestic lithium producer and relied on imports for more than half the lithium used last year, a situation that contributed to lithium's inclusion on the USGS's 2025 List of Critical Minerals. World lithium production has grown more than 40 times over the past 30 years, driven by demand for lithium-ion batteries. The USGS projects that world production capacity will double again by 2029.
North Carolina's Kings Mountain and Hallman-Beam mines previously produced lithium from pegmatites but closed in the 1990s when production shifted to lower-cost sources in South America and Australia. The United States was the dominant world lithium producer three decades ago when those mines were active. Australia remains the world's largest producer today, with China second and accounting for the majority of world lithium refining and consumption.
USGS Director Ned Mamula said the research "shows that the Carolinas contain enough lithium to help meet the nation's growing needs — a major contribution to U.S. mineral security, at a time when global lithium demand is rising rapidly." He added that USGS mineral science represents "the leading edge in the effort to restore America's mineral independence" and noted that the United States "was the dominant world producer of lithium three decades ago when North Carolina's lithium mines were active."
Several verified sources, together with artificial intelligence, were used in the preparation of this article. The content was reviewed by our editorial team prior to publication. Disclosure provided in accordance with Article 50 of the EU Artificial Intelligence Act (AI Act).
