Zirconolite
Black crystal aggregates of the rare zirconium mineral zirconolite.
General
Category	Oxide minerals
Formula (repeating unit)	CaZrTi 2 O 7
IMA symbol	Zrc [1]
Strunz classification	4.DH.30
Crystal system	2M polytype: monoclinic 3O polytype: orthorhombic 3T polytype: trigonal
Crystal class	2M polytype: prismatic (2/m) 3O polytype: dipyramidal (mmm (2/m 2/m 2/m)) 3T polytype: trapezohedral (3 2)
Identification
Color	Black to brown, red
Luster	Resinous, sub-Metallic
Streak	Dark brown, brownish yellow
Diaphaneity	Translucent, opaque
References	[2]

Zirconolite is a mineral, calcium zirconium titanate ; formula CaZrTi ₂ O ₇ . Some examples of the mineral may also contain thorium , uranium , cerium , niobium and iron ; the presence of thorium or uranium would make the mineral radioactive . It is black or brown in color. ^[3]

References [ edit ]