Coming Soon • Spring 2027

GreenStarstone

180 Years with Michigan’s State Gem

The first complete exploration of chlorastrolite, Michigan’s mesmerizing green gem.

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Published by Wolverine Gems, an imprint of Opalus LLC

Front-view hardcover book mockup of Green Starstone

The Book

Michigan’s Most Beautiful Secret

Since its discovery, Michigan’s green starstone – known variously as chlorastrolite, greenstone, or the whimsical “turtle agate” – has captivated collectors and jewelers with its unique patterns and rich chatoyancy.

This is the first book to fully document its story: from the dramatic geology of its formation through its discovery and rise, fall, and rediscovery by the jewelry industry; the science behind its optical properties; sourcing and cutting gem-quality stones; and interviews with the people who have kept it alive.

“A remarkable place.
A remarkable stone.”

Complete History

From discovery to gilded age to modern works

Engraved rough chlorastrolite among rock

The Science

A study of its formation and unique structure

Engraving of an underground mine passage

The Field

Interviews with miners, cutters & jewelers

Meet the Author

Derrick Sobodash

A former journalist turned gem cutter and jeweler, Derrick Sobodash brings more than a decade of hands-on experience digging, cutting, and working with Michigan chlorastrolite.

He teaches lapidary and faceting classes and operates a shop in downtown Rochester, Michigan. His family’s first gem shop, located in Beijing, introduced chlorastrolite and other Great Lakes gemstones to customers in China.

This book is the culmination of years of historical research, oral history, and fieldwork across the Upper Peninsula. It is intended to be both a passionate tribute and the definitive reference on Michigan’s state gem.