Keweenaw Greenstone (Chlorastrolite) set in sterling silver with copper accents.
Michigan Greenstone is a rare treasure! This Michigan State Gem is commonly called "Greenstone". The correct mineral name is Chlorastrolite. It is found chiefly as small rounded pebbles on the beaches of Isle Royale in Lake Superior and also throughout the Keweenaw Peninsula associated with the native copper deposits. It has been prohibited to take Greenstones from Isle Royale since 2000, which is what added to the value of the stones.
