Cuprite

The Milpillas will certainly go down as one of the finest localities for azurites , brochantite and cuprite worldwide. A contemporary locality that is now tapped out. The cuprites were never terribly plentiful, but certainly the very best that Mexico has ever produced. In artificial light they appear metallic, but given daylight or a good backlight they are blood red. Most specimens formed in relatively tight seams, so the crystals tend to be flattened and close to the matrix. Very few had the presentation this one has, with the crystals sitting up on the white matrix. Outstanding!

Locality: Milpillas Mine, Municipio de Santa Cruz, Sonora Mexico

Composition: Copper Oxide