THE MINERAL MIARGYRITE

Chemistry: AgSbS2, Silver Antimony Sulfide
Class: Sulfides
Subclass: Sulfosalts
Uses: Mineral specimens and as a minor ore of silver.
Specimens

Miargyrite is a another interesting silver sulfide mineral that is popular with collectors who love to collect silver bearing minerals. Other silver sulfide minerals include stephanite, pyrargyrite, polybasite, proustite, argyrodite, andorite and acanthite among many others. It is easy to confuse miargyrite with some of these other minerals, but its crystal habit and unusual streak will generally suffice to differentiate it. Miargyrite is a sulfosalt, a segment of sulfides where the antimony acts more like a metal than a non-metal and occupies a position where it is bonded to sulfurs.

PHYSICAL CHARACTERISTICS:

Color is iron black to steel gray.
Luster is metallic.
Transparency: Crystals are opaque.
Crystal System: Monoclinic; 2/m.
Crystal Habits include complex crystals with a tabular character and massive.
Cleavage: Not discernible.
Fracture: Conchoidal.
Hardness is 2 - 2.5
Specific Gravity is 5.1 - 5.3 (somewhat heavier than average for metallic minerals)
Streak is cherry-red.
Other Characteristics: Specimens will darken with exposure to light.
Associated Minerals include pyrargyrite, polybasite, proustite, galena, chalcopyrite and acanthite.
Notable Occurrences include Saxony and the Harz Mountains of Germany; Pribram, Czech Republic; San Juan, Colorado; Silver City, Idaho; Cerbat Mountains, Arizona and California, USA; Romania; Chile and Bolivia.
Best Field Indicators are crystal habit, streak, softness, color and luster.