Heitgaasite

Heitgaasite is a rare mineral discovered in 2017, named after the Dutch mineralogist and geologist, Jan Heitgaas. It is a copper-arsenic sulfide with the chemical formula Cu12As4S13. Heitgaasite is typically found in the oxidized zones of copper deposits, often associated with other copper minerals such as enargite and tennantite. It forms prismatic crystals, usually in the form of aggregates or crusts, and can exhibit a metallic luster. The mineral is dark gray to black in color and has a hardness of approximately 3.5 on the Mohs scale. Heitgaasite is of interest to mineral collectors and researchers due to its rarity and unique chemical composition. It is not known to have any significant industrial applications.