Minerals and Geology

Geologic Overview

The Kootenai National Forest is underlain by the Belt Supergroup. Rock in these formations is over 800 million years old, and was created when sedimentary layers deposited by a large inland sea lithified, or hardened, into rock. Exposures of the Prichard formation of the Belt Supergroup are found throughout the KNF.  Stone from this formation, composed primarily of metamorphosed silts and muds, is sought after for use as building and landscaping stone.  The Montanore ore body is located in the Revett formation of the Belt Supergroup.

KNF Rocks and Minerals

Mining Projects