Davidite
Davidite is a rare earth oxide mineral with chemical end members La and Ce. It exists in two forms:
- Davidite-(La) (La,Ce,Ca)(Y,U)(Ti,Fe3+
)
20O
38 discovered at Radium Hill mine, South Australia in 1906 and named by Douglas Mawson for Australian geologist Tannatt William Edgeworth David (1858-1934). - Davidite-(Ce) (Ce,Le)(Y,U)(Ti,Fe3+
)
20O
38 first described in 1960 from Vemork, Iveland, Norway.
| Davidite-(La) | |
|---|---|
Davidite-(La) from Kazakhstan | |
| General | |
| Category | Oxide minerals |
| Formula (repeating unit) | (La,Ce,Ca)(Y,U)(Ti,Fe3+ ) 20O 38 |
| IMA symbol | Dvd-La |
| 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 |
| Other characteristics | Radioactive |
| References | |
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