ARGYRODITE, a mineral which is of interest as being that in which the element germanium was discovered. It is a silver sulpho-germanate, and crystallizes in the cubic system. The botryoidal crusts of small indistinct crystals first found in a silver mine at Freiberg in Saxony were originally thought to be monoclinic, but were afterwards proved to be identical with the more distinctly developed crystals found in Bolivia. The colour is iron-black with a purplish tinge, and the lustre metallic. Hardness 21, specific gravity 6.2. Isomorphous with argyrodite is the cor responding tin compound also found in Bolivia as cubic crystals, and known by the name canfieldite.