V is for Variscite
Variscite is a somewhat rare mineral of hydrated aluminum phosphate. It is often confused with turquoise both because it can be found in the same locations and because of similarity in color to some types of turquoise.
Variscite has an interesting range of green colors due to the presence of trivalent chromium. While there are no real industrial uses for vasiscite, trivalent chromium is used in chrome plating. It is a much less toxic alternative to use rather than hexavalent chromium which is a known carcinogen.
The term variquoise has been used when an easy determination cannot be made between variscite and turquoise or when both variscite and turquoise coexist in the same rock.
There is no known toxicity with variscite, but as always, be safe when handling any mineral. It is a very soft material (3.5 – 4.5 on the Mohs scale) so it is not a good gemstone choice for rings which are often more susceptible to their environment. Being opaque, it is cut into cabochons or used as carving material.
This specimen from Utah is in the permanent collection at the Smithsonian.