- Sweetwater Mine (Milliken Mine; Frank R. Milliken; Blair Creek; Ozark Lead Company Mine; Adair Creek; Logan Creek), Ellington, Viburnum Trend District, Reynolds Co., Missouri, USA
- Cabinet, 11.4 x 5.8 x 1.7 cm
Chalcopyrites are common from this locality, but this specimen stands out above the others, for a couple of reasons. First, the crystals (to one centimeter) are beautifully isolated on the matrix, and they are very sharp. They also have this beautiful, colorful iridescence that the camera does not pick up all that well. From the noted mid-west, George Feist collection.