- Calcite, Sphalerite, Chalcopyrite
- Mid-Continent Mine, Treece, Picher Field, Tri-State District, Cherokee Co., Kansas, USA
- Small Cabinet, 5.5 x 4.5 x 3.5 cm
A very old, very rare calcite crystal with sparkly, powder-blue copper mineral inclusions from the Mid-Continent Mine of Kansas. The sharply terminated, lustrous, translucent, amber crystal scalenohedron aesthetically rests on sphalerite with chalcopyrite. The copper mineralization, as malachite or chrysocolla, formed as the chalcopyrite weathered and as the calcite crystal was growing. This is a unique, rare old-time specimen, certainly from prior to World War I. Ex. Mullane Collection.