Fourmarierite

Fourmarierite
Uraninite covered with red hexagonal fourmarierite crystals
General
Category	Oxide minerals
Formula (repeating unit)	Pb(UO2)4O3(OH)4•4H2O
Strunz classification	4.GB.25
Crystal system	Orthorhombic
Crystal class	Pyramidal (mm2) H-M Symbol: (mm2)
Space group	Bb21m
Identification
Color	Red, golden-red, brown
Cleavage	On {001}, perfect
Mohs scale hardness	3 - 4
Luster	Adamantine
Diaphaneity	Transparent
Density	6.046 g/cm3

Fourmarierite is a secondary uranium-lead mineral. It was named for the Belgian geologist Paul Fourmarier (1877–1970). Its chemical formula is Pb(UO₂)₄O₃(OH)₄•4H₂O.