There are only about 20 minerals that consistently contain germanium of which the more common are the sulfides argyrodite, germanite and renierite . Sn , in canfieldite. A series is where two or more minerals show substitution with one or more elements in their chemistries, but the structure is essentially the same. Both these minerals have been classified as sulfosalts , but this is not universally accepted. Luster is metallic.
Crystals are opaque.
Streak is gray. Notable Occurrences are limited to the type locality of Himmelsfurst Mine, Freiberg, Saxony , Germany as well as Oruro, Bolivia. Associated Minerals include acanthite , pyrite and other sulfides . Best Field Indicators are crystal habit, locality, color, lack of cleavage and density.