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An Isle Royale Greenstone Cabochon .7 grams
Gs775
New
Here’s a very nice Isle Royale Greenstone, with Thomsonite dotted across the surface. Round, cute, beautifully patterned, and nicely domed, this would be a perfect ring stone.
.7 grams
9mm round, dome 6mm
1 Item
Unique Item
More info
Dotted with pink bits of Thomsonite, round, nicely sized, this Isle Royale Greenstone is just right for a ring or pendant. It's a beauty, don't hesitate.
The Michigan State Gem is commonly called "Greenstone", "Michigan Greenstone" or "Isle Royal Greenstone". The correct mineral name is Chlorastrolite, a variety of pumpellyite. Chlorastrolite is found as small pebbles on the beaches of Isle Royale in Lake Superior and also throughout the Keweenaw Peninsula. Greenstone is associated with the native copper deposits of Northern Michigan. The Michigan Greenstones are found as green/black nodules in vesicles of the amygdaloidal basalts. Most greenstones are smaller than a pea, and really large ones are extremely rare.
