The only instrument of its kind in the world.... this is a lithophone made from Michigan's State Stone, the Petoskey Stone. The Petoskey stone is a fossilized colony coral from the Devonian Age... 350 million years ago it was a living organism, a hexagonaria percarinata. This single octave diatonic instrument was made by musician and edutainer, Tom Kaufmann. For more information, go to http://www.tinkertunes.com/Lithophones