An Arkansas company that has been drilling in eastern Idaho for rare earth minerals plans to expand its search by going across the border to western Montana.

Lonoke-based U.S. Rare Earths said Thursday it plans in May to start drilling for core samples in the Sheep Creek area on Lemhi Pass in Montana.

Rare Earths President Dan McGroarty says western Montana has potential because eons of geologic activity have exposed layers that would otherwise be far below the surface. He also says the area contains extensive records from previous geologists searching for precious metals.

On the Idaho side, the company has been drilling in the Salmon-Challis National Forest. It's unclear what the company has found. Rare earth minerals are used in consumer electronics and other products.