“Nice Michigan classic with several glassy translucent colorless calcite crystals in a cluster with crystallized native copper. Very slight chipping present, this still in very good condition and shows some local color in calcite from the included copper. Complete all around. Don Windeler collection, acquired 2021 from Dan Weinrich. Ex-Martin Jensen. Previous label notes that at one time this was part of the collection of Samuel Brady at the Mackay School of Mines in Reno, Nevada, traded from Tom Lugaski on 22 Dec 1989. The piece was likely collected pre-1900. ”