Silica Quarry, Rockwood, Wayne Co., Michigan, United States.
A sharp thumbnail of celestite from a locality inside the Detroit metro area. This piece was collected at least 20 years ago, and has beautiful phantoms, above average transparency, and a sharp termination. Michigan celestites are not exactly rare (at least at shows in the Midwestern US) but even there they are outnumbered by pieces from Madagascar, and its not really often hat I see a particularly nice thumbnail.
The black piece of paper is to help provide grater contrast for the photograph-- the phantom is perfectly clear in person, but the crystal was nearly impossible to photograph against a white background.