To learn more about the mineralogy of the allanite, see Mindat.ord
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Allanite
- Translations : Allanite
- Synonym : Cerepidote, Cerorthite
- Etymology : From Thomas ALLAN, Scottish mineralogist who discovered this mineral (1777-1833).
- Discovery: 1810 by Thomas Allan (1777-1833), Scottish mineralogist
- Type localityQáqarssuatsiaq, Aluk Island, Kap Farvel, Kujalleq, Groenland
Gemological data
- Chemical formula : (Ce,Ca,Y)2 (Al,Fe+2,Fe+3)3 (SiO4)3 (OH)
- Hardness (Mohs) : 5,5/6
- Density : 3.5/4.2
- Refractive index : nα = 1.715 - 1.791 nβ = 1.718 - 1.815 nγ = 1.733 - 1.822
- Crystal system : Monoclinic
- Group : Epidote
- Mineralogical Class : Sorosilicates
