Schsiteita

Schsiteita is a rare mineral species classified within the sulfide mineral group. It has a chemical composition primarily consisting of zinc, copper, and sulfur, denoted as Zn3CuS4. This composition indicates that schsiteita contains zinc, copper, and sulfur atoms, which are arranged in a particular crystal structure.

Schsiteita was first described in 2017 and is most commonly found in the trans-Alaska pipeline region, in the Sitka Sound area of Alaska, USA. The mineral has also been identified in minor quantities in other locations worldwide, including Mexico and Australia.

The mineral exhibits a distinctive greenish-blue to blue color, often accompanied by a slight whiteness due to the size and distribution of its crystals. The overall appearance can resemble powdery coatings or thin films on surrounding rocks.

Schsiteita is notable for its mixed valence composition, featuring both Cu+ and Cu2+ ions. These ions are responsible for the mineral's unique coloration and involved in the formulation of its chemical bonds. In terms of hardness, schsiteita has been reported to range between 1.5 and 2 on the Mohs hardness scale.

Due to its rarity and small size of disseminated or epitaxial crystals, preparing and studying schsiteita specimens can be challenging. The support of specialized microscopic techniques and experimental apparatus is often required for detailed mineralogical analysis and identification.