Outstanding pale brown sharp crystals of the rare mineral paramontroseite, a simple vanadium oxide, from the type locality (Bitter Creek Mine, Long Park, Montrose County, Colorado, United States of America), on a contrasting dark matrix. — Photo: David Hospital · CC BY-SA 4.0
Paramontroseite
An orthorhombic vanadium(IV) oxide of the ramsdellite group — its synthetic form interests battery researchers.
Intro adapted from Wikipedia (CC BY-SA).
Paramontroseite is an IMA-recognized mineral species in the vanadate class, with the chemical formula VO₂.
It crystallizes in the orthorhombic crystal system (space group Pbnm). It is a member of the Ramsdellite structural group.
Key properties: specific gravity 4.09; Black streak; Submetallic luster.
IMA symbol Pmto, grandfathered status — known before the IMA’s founding, named in 1955.
Found in relatively unoxidized Colorado Plateau-type U–V ores in sandstones, formed by dehydrogenation of montroseite (Colorado, Utah, and Arizona, USA).
It is found associated with Montroseite, corvusite.
Its name comes from the Greek for near, for its paramorphic relation to montroseite.