The U.S. Geological Survey announced Tuesday that the Appalachian region contains an estimated 2.3 million metric tons of undiscovered, economically recoverable lithium. This amount equals 328 years of U.S. lithium imports based on last year's consumption levels.

Lithium, found in pegmatites similar to granite, occurs in about 1.43 million metric tons in the southern Appalachians, mainly in the Carolinas, and 900,000 metric tons in the northern section, concentrated in Maine and New Hampshire. These reserves could supply batteries for 130 million electric vehicles or 1.6 million grid-scale batteries. "This research shows that the Appalachians 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," USGS Director Ned Mamula said.

USGS geologists combined geologic maps, tectonic history, geochemical sampling, geophysical surveys, and mineral records with simulations using a global dataset of lithium pegmatites to produce the estimates. The figures represent a 50% confidence level. In the northern Appalachians, there is 90% confidence of at least 90,000 metric tons remaining undiscovered and a 10% chance of up to 7.4 million metric tons.

Lithium pegmatites in the Appalachians formed over 250 million years ago during the collision of continents that created Pangea. The Kings Mountain area in North Carolina hosted the first large-scale U.S. lithium pegmatite mine, and the United States led global production three decades ago.

The U.S. had one domestic lithium producer last year and imported more than half its supply, with additional lithium arriving in finished products like batteries. Australia leads world production, while China dominates refining and consumption. USGS projects global lithium production capacity will double by 2029 amid surging demand from electric vehicles and energy storage.

Lithium powers lithium-ion batteries in vehicles, electronics, military gear, and grid storage, as well as aerospace alloys. The assessments support Executive Orders aimed at boosting American mineral production and restoring U.S. leadership. Separately, USGS estimated 5 to 19 million metric tons of lithium in Arkansas brines in 2024.