Zirkelite

Zirkelite
General
CategoryOxide mineral
Formula(Ti,Ca,Zr)O(2−x)
IMA symbolZke
Strunz classification4.DL.05
Crystal systemIsometric
Crystal classHexoctahedral (m3m)
H-M symbol: (4/m 3 2/m)
Unit cella = 5.02 Å, Z = 4
Identification
ColorBlack, reddish brown
Crystal habitCrystalline, metamict, pseudocubic
CleavageNone
FractureBrittle
LusterResinous
StreakBrownish grey
DiaphaneitySubtranslucent to opaque
Density4.7
Other characteristics Radioactive

Zirkelite is an oxide mineral with the chemical formula (Ca,Th,Ce)Zr(Ti,Nb)2O7. It occurs as well-formed fine sized isometric crystals. It is a black, brown or yellow mineral with a hardness of 5.5 and a specific gravity of 4.7.