Mount Diablo Mine, Mount Diablo, Clayton, Diablo Range, Contra Costa Co., California, USA
Cabinet, 14.4 x 13.4 x 4.8 cm
At nearly 930 grams, this is a HUGE and significant example of this rare species, from perhaps its most classic old locality as far as actualy display-quality specimens go. This specimen is covered by a blanket of fat, thick crystals to 6mm, a thousand of them. It was traded to me by a collector who got it some time ago through an exchange with the California Institute of Technology's collection. Ugly perhaps, but for size and location, an important California specimen.