Callaghanite - Premier Chemicals Mine, Gabbs, Nye County, Nevada, USA

40 x 35 x 15mm
 
Rare copper Magnesium Carbonate showing as blue micro crystals on areas of the matrix. The crystals are quite adamantine and bright with clearly defined faces under magnification.
This is the Type Locality for Callaghanite, which is named after the Director of the New Mexico Bureau of Mines, Dr Eugene Callaghan, in recognition of his work on Magnesite deposits.