What is "miargyrite"

Miargyrite \Mi*ar"gy*rite\, n. [Gr. ? less + ? silver. So called because it contains less silver than some kindred ore.] (Min.) A mineral of an iron-black color, and very sectile, consisting principally of sulphur, antimony, and silver.

n. (context mineralogy English) A sulfide of silver and antimony.

Miargyrite is a mineral, a sulfide of silver and antimony with the formula Ag Sb S. It is a dimorph of cuboargyrite. Originally discovered in the Freiberg district of Germany in 1824, it has subsequently been found in many places where silver is mined. It usually occurs in low temperature hydrothermal deposits. and forms black metallic crystals which may show a dark red internal reflection. The streak is also red.

Miargyrite is named from the Greek meyon, "smaller" and argyros, "silver," as its silver content is lower than most silver sulfides.