Davidite-(La) | |
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Davidite-(La) from Kazakhstan
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General | |
Category | Oxide minerals |
Formula (repeating unit) |
(La,Ce,Ca)(Y,U)(Ti,Fe3+)20O38 |
Strunz classification | 4.CC.40 |
Crystal system | Trigonal |
Crystal class | Rhombohedral (3) H-M symbol: (3) |
Space group | R3 |
Unit cell | a = 10.376, c = 20.91 [Å]; Z = 3 |
Identification | |
Color | Black |
Fracture | Subconchoidal to uneven |
Tenacity | Brittle |
Mohs scale hardness | ~6 |
Luster | Vitreous |
Diaphaneity | Opaque, translucent in very thin fragments |
Specific gravity | 4.33 to 4.48 |
Alters to | Metamict |
References |
Davidite is a rare earth oxide mineral with chemical end members La and Ce. It exists in two forms: