Sphalerite with Chalcopyrite

I do love a good sphalerite, and THIS is a good sphalerite. The prominant crystal is complete and is 4.5cm X 2.5cm thick. There is wonderful color play in the light. The sister crystals are also complete save the bottom contact area. A perfect amount of chert sets them off. The generous sprinkling of chalcopyrites enhance.

Locality: Tri-State Mining District, Joplin Missouri

Composition: zinc sulfide