- Toenail, 3.0 x 1.3 x 1.8 cm
- Chanarcillo, Copiapo Province, Atacama Region, Chile
A fine, classic, gemmy proustite crystal from the most desirable locality, circa the late 1800s and early 1900s. Proustite, in the form of large crystals from this locale, was one of the single most treasured items in any early 1900s and late 1800s cabinet of minerals. Today, they are very rare teeth and come about only in old collections as they recycle. This is an outstanding thumbnail for the sharp crystallography and large size relative to the specimen, of its dominant 2.4-cm-tall crystal. When backlit it glows a deep red. When strongly backlit, it is transparent and gemmy.