The Appalachian mountain range could be the key to America’s lithium supply. A recent USGS scientific paper published in Natural Resources Research found an estimated 2.3 million metric tons of lithium oxide across the region.

The southern Appalachians hold an estimated 1.43 million metric tons of lithium oxide, concentrated in the Carolinas. The northern Appalachians hold an estimated 900,000 metric tons, concentrated in Maine and New Hampshire. This lithium sits in pegmatites, which are large-grained rocks similar to granite.

USGS researchers combined geologic maps, tectonic history, and geochemical sampling to make these estimates. These pegmatites formed more than 250 million years ago when plate tectonics forced Africa, Europe, and North America together into Pangea.

The United States had only one producer of lithium and relied on imports for more than half of the lithium used last year. Because of this, lithium made the 2025 List of Critical Minerals. Global demand is rising, and the USGS expects world production capacity to double by 2029.

Lithium Production That Powers the Future

The 2.3 million metric tons of lithium in the Appalachian region can help you see the scale of this resource. Here’s what this amount can power:

• 1.6 million grid-scale batteries are large enough to stabilize an electric grid

• 130 million electric vehicles

• 180 billion laptops, or a 1,000 year-supply of laptops for the world (at 2025 levels)

• 500 billion cellphones, or 60 cellphones for each person on earth

USGS Director Ned Mamula sees this as a major step toward U.S. mineral independence.

“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,” said USGS Director Ned Mamula.

“USGS mineral science is the leading edge in the effort to restore America’s mineral independence by mapping our nation’s mineral resources,” He added. “Everything else follows on the science: permitting reform and other policy changes to support investment in clean, responsible mining to 21st century standards, and mining workforce training for new American jobs. The United States was the dominant world producer of lithium three decades ago, and this research highlights the abundant potential to reclaim our mineral independence.”

The USGS also studies other sources of lithium. In 2024, researchers assessed that a resource of 5 to 19 million metric tons is present in brines in the Smackover Formation of southwest Arkansas.