Isle Royale Greenstone

Isle Royale Greenstone (CHLORASTROLITE) is Michigan's distinctive state gem. Chlorastrolite is a variety of Pumpellyte which sometimes fills vesicles (holes) in Keweenawan Basalts as well as basalts on Isle Royale. Collecting Greenstone in Isle Royale National Park is strictly prohibited, but this lovely chatoyant gemstone can still rarely be discovered on the beaches and mine dumps of the Keweenaw Peninsula IF you know where to look.

Chlorastrolite can be translated from its Greek roots as "Green, Star-like, Stone". Chlorastrolite is one of the rarest gemstones on earth.