Euxenite | |
---|---|
General | |
Category | Oxide minerals |
Formula (repeating unit) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti) 2O 6 |
IMA symbol | Eux[1] |
Strunz classification | 4.DG.05 |
Crystal system | Orthorhombic |
Space group | Pcmn (no. 62) |
Identification | |
Color | Black, brownish black, greenish black |
Crystal habit | Massive, anhedral crystals in matrix |
Twinning | Common on [201] |
Cleavage | None |
Fracture | Conchoidal to subconchoidal |
Mohs scale hardness | 5.5 to 6.5 |
Luster | Brilliant submetallic, waxy to resinous on fractures |
Streak | Yellowish, grayish, or reddish brown |
Diaphaneity | Opaque, translucent on thin edges |
Specific gravity | 4.7 to 5 |
Optical properties | Isotropic |
Refractive index | n = 2.06 – 2.24 |
Other characteristics | Metamict – originally crystalline, now amorphous due to radiation damage. Radioactive |
References | [2][3][4] |
Euxenite, or euxenite-(Y) (the official mineralogical name), is a brownish black mineral with a metallic luster.