RHH's photos with the keyword: hexagonaria

I believe these are Charlevoix Stones, a fossil coral we picked up along the shores of Lake Huron. We will probably polish some of them and use them for jewelry.

Petosky stones are fossilized coral that can be found along the shores of Lake Michigan and Lake Huron. They are the state stone of Michigan and are often made into jewelry. My wife, who picks up stones everywhere came home with a bag of them.