Urusovite

Urusovite is a rare copper aluminium arsenate mineral with formula: CuAlAsO5. It is a monoclinic-prismatic light green mineral.

Its type locality and only reported occurrence is in the Novaya fumarole, Second scoria cone, North Breach, Great Fissure eruption, Tolbachik volcano, Kamchatka Oblast', Far-Eastern Region, Russia. It was named after Vadim Sergeevich Urusov, crystal chemist of Moscow State University. It was approved by the International Mineralogical Association in 1998.