Piikiteen

Piikiteen is a rare mineral species discovered in 2009. It is a copper-arsenic sulfide with the chemical formula Cu11As4S13. The mineral was first found in the Piikiteen mine in the Khibiny Massif, Kola Peninsula, Russia. Piikiteen is named after the mine where it was discovered.

The mineral crystallizes in the monoclinic crystal system and typically forms small, prismatic crystals. It has a metallic luster and a dark gray to black color. Piikiteen is brittle and has a Mohs hardness of approximately 3.5. It is often associated with other sulfide minerals such as chalcopyrite and pyrrhotite.

Piikiteen is of interest to mineralogists and collectors due to its rarity and unique chemical composition. It is not known to have any significant industrial applications. The mineral's discovery has contributed to the understanding of the complex mineralogy of the Khibiny Massif and the processes involved in the formation of sulfide deposits in this region.