Barite – BaSO₄

Barite, is a common hydrothermal mineral. It may also be deposited by cold groundwater solutions. The crystallization is orthorombic. Quite commonly, as in this specimen, crystals are flattened parallel to the basal pinacoid, and terminated on the edges by prism faces. Cleavages parallel both the base and the prism.

Lawrence University collection, information from card