Cavansite clusters in Quartz and sediment from the Pune region of southern India.

Cavansite is a hydrated calcium-vanadium silicate with the chemical formula Ca(V5+O)Si4O10·4H2O. This phyllosilicate, which belongs to the mica group, shows a green to dark blue color with a glassy luster, a blue-white stripe color and good cleavage along the [010] crystal plane. It has an average density of 2.25 and a hardness of 3 to 4. The crystal system is orthorhombic, and the mineral is not radioactive. The name cavansite is taken from the elements calcium, vanadium and silicon in its composition. Cavansite is found primarily in secondary mineralizations in andesites and basalts, with the type locality being the Owyhee Dam area in Malheur County, Oregon, USA. The Wagholi Quarry near Pune in India is today the main site.