4.4" Arsenopyrite Crystal Cluster - Peru

Arsenopyrite is an iron arsenic sulfide with the chemical formula FeAsS. It is the most common arsenic-bearing mineral and is its principal ore, and can be found in igneous, metamorphic and sedimentary rock. Crystals can be found as prismatic, twinned, columnar, elongated and massive formations within veins and are found in locations all around the world. Depending on minerals present during formation, the iron in arsenopyrite can be replaced by cobalt, forming cobaltite.

Arsenopyrite contains a significant amount of poisonous arsenic, making it somewhat toxic. Washing hands following handling is recommended.