VOLBORTHITE on BARYTE and GYPSUM

Volborthite (green mineral) is an extremely rare mineral composed of copper and vanadium, represented by the chemical formula Cu3V2O7(OH)2·2H2O. Discovered in 1838 in the Urals, it was initially named knaufite but was later renamed in honor of the Russian paleontologist Alexander von Volborth (1800–1876). 

 Volborthite is an extremely rare oxidation mineral found in vanadium-rich hydrothermal copper ores, often occurring alongside minerals such as brochantite, malachite, atacamite, tangeite, chrysocolla, baryte, and gypsum.

Tangeite, also known as calciovolborthite, has the formula CaCuVO4(OH) and is closely related to volborthite. The mineral was first identified in 1837 at the Sofronovskii Mine in Yugovskii Zavod, located in the Perm region of the Middle Urals, Russia.