MIARGYRITE
Specimen mia-1

Dims: 1.3 x 1.2 x 1.1" (3.2 x 3.0 x 2.7 cm)

Wt: 1.3 oz. (37 g)

Kelly Mine, Red Mountain, Randsburg Mining District, San Bernardino County, California, U.S.A.

Massive Miargyrite makes up the bulk of this small hand specimen. This sulfosalt shows no crystal form and has the dark silvery-gray color and metallic luster that is common in most silver-bearing sulfides. It probably occurred as veins in the brown and white quartz matrix that is present in the piece.

Dims: 1.1x0.7x0.6" (2.8x1.7x1.5 cm)

Wt: 0.46 oz. (13.1g)

San Genare, Huancavelica, Peru

This miargyrite thumbnail is a thick crust of tiny crystals on a base of another silver sulfide, with a tiny amount of other minerals present. The crystals of miargyrite are so tiny that they appear as a field of sparkles unless a high power loupe is used, which resolves them into silvery flattened crystals with good form - they are rounded and the faces have a slight convex curvature. The host mineral (about 50% by weight) is a vein of another silver sulfosalt, which I believe is polybasite. It has a superficially metallic appearance, and under a loupe it appears translucent and deep cherry red, with deep red reflections from internal fractures.