Tugarinovite

Tugarinovite is a rare molybdenum oxide mineral with formula MoO₂. It occurs as a primary mineral phase associated with metasomatism in a sulfur deficient reducing environment. In the type locality it occurs with uraninite, molybdenite, galena, zircon and wulfenite.^[2]

Tugarinovite
Tugarinovite
General
Category	Oxide mineral
Formula	MoO2
IMA symbol	Tug[1]
Strunz classification	4.DB.05
Crystal system	Monoclinic
Crystal class	Prismatic H-M symbol (2/m)
Space group	P21/c (no. 14)
Unit cell	a = 5.6 Å, b = 4.85 Å, c = 5.53 Å; β = 119.37°
Identification
Color	Dark lilac-brown
Crystal habit	Crystals are tabular striated prisms
Twinning	Polysynthetic
Mohs scale hardness	4.6
Luster	Greasy to metallic
Streak	Greenish gray
Diaphaneity	Semitransparent
Specific gravity	6.58 (calculated)
Optical properties	Biaxial
Pleochroism	Light gray to dark pink; pale yellow to bluish olive-brown in reflected light
References	[2][3][4]

Tugarinovite was first described for an occurrence in the Lenskoye molybdenum–uranium deposit in the Amurskaya Oblast, Far-Eastern Region, Russia. It was named for geochemist Ivan Alekseevich Tugarinov of the Vernadskii Institute in Moscow.^[2][3] In addition to its type locality in Russia it has been reported from the Allende meteorite in Chihuahua, Mexico, the Nansei Archipelago of Japan and Bohemia in the Czech Republic.^[3]