Sphalerite

I remember back in the mid-1990s when I saw a similar specimen and had to have it. Unfortunately ny good friend grabbed it first and I had to visit it at his house. The largest crystal is 3.5cm, and they have the look and luster of coal.  Remarkably, not a single bit of contact or damage. Some dolomites accent the specimen and a lone, songle doubly terminated prismatic calcite anchors the one end. Ex Jim and Paula Wilson.

Locality: Tri-State, Joplin, Missouri

Composition: zinc sulfide