Cerianite-(Ce)
| Cerianite-(Ce) | |
|---|---|
| General | |
| Category | Oxide |
| Formula (repeating unit) | (Ce,Th)O2 |
| Crystal system | Isometric - Hexoctahedral (point group m3m) |
| Space group |
Isometric Space group Fm3m |
| Unit cell | a=5.42 [Å] |
| Identification | |
| Color | Dark greenish amber-yellow, yellow, buff |
| Crystal habit | octahedra; earthy, massive |
| Diaphaneity | Translucent or transparent |
| Density | 7.20 (synth. material, calc.; approximated) |
| References | [1][2] |
Cerianite-(Ce) is a relatively rare oxide mineral, belonging to uraninite group with the formula (Ce,Th)O2.[3][2] It is one of a few currently known minerals containing essential tetravalent cerium, the other examples being stetindite and dyrnaesite-(La).[4][5]
Occurrence and association
Cerianite-(Ce) is associated with alkaline rocks, mostly nepheline syenites.[1] It may be found in carbonatites.[2] Cerianite-(Ce) associates with minerals of the apatite group, bastnäsite-group minerals, calcite, feldspar, "fluocerite", "hydromica", ilmenite, nepheline, magnetite, "törnebohmite" and tremolite.[1] It is the most simple cerium mineral known.[2]
Notes on chemistry
Beside thorium cerianite-(Ce) may contain trace niobium, yttrium, lanthanum, ytterbium, zirconium and tantalum.[1]
Crystal structure
For details on crystal structure see cerium(IV) oxide.
References
- 1 2 3 4 "Cerianite-(Ce) - Handbook of Mineralogy" (PDF). Handbookofmineralogy.org. Retrieved 2016-03-04.
- 1 2 3 4 "Cerianite-(Ce): Cerianite-(Ce) mineral information and data". Mindat.org. Retrieved 2016-03-04.
- ↑ Graham, A.R., 1955. Cerianite CeO2: a new rare-earth oxide mineral. American Mineralogist 40, 560-564
- ↑ "Stetindite: Stetindite mineral information and data". Mindat.org. Retrieved 2016-03-04.
- ↑ "Dyrnaesite-(La): Dyrnaesite-(La) mineral information and data". Mindat.org. Retrieved 2016-03-04.