A solid, old-time and fine specimen of the rare sulfate, krohnkite, from the Type Locality, the Chuquicamata Mine of Chile. This specimen exhibits the most intense teal blue color. And the variation in blue color, in itself, is very noteworthy. The piece exhibits what is highly unusual for the species, having blocky, cavernous, crystal form. The usual classic for the species are lamellar growth of curved crystals in parallel bundles. Ex. George Elling Collection.