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Biotite from
Ambatomena ruby deposit, Isoanala, Betroka District, Anosy, Madagascar


Locality type:Deposit
Classification
Species:'Biotite' (not an IMA approved species)
Formula:K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Age information
Maximum recorded age:487 ± 4 Ma
Minimum recorded age:487 ± 4 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
1487 ± 4 MaFurongian - Ar – Ar biotite
Sample references:
1 -
Rakotondrazafy, Amos Fety Michel; Giuliani, Gaston; Ohnenstetter, Daniel; Fallick, Anthony E.; Rakotosamizanany, Saholy; Andriamamonjy, Alfred; Ralantoarison, Théogène; Razanatseheno, Madison; Offant, Yohann; Garnier, Virginie; et al. (2008) Gem corundum deposits of Madagascar: A review. Ore Geology Reviews, 34 (1-2). 134-154 doi:10.1016/j.oregeorev.2007.05.001
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Ambatomena ruby deposit, Isoanala, Betroka District, Anosy, Madagascar
Data Identifiers
Mindat Occurrence Record ID:1224835
Long-form Identifier:1:3:1224835:7
GUID (UUID V4):0
References
Rakotondrazafy, Amos Fety Michel; Giuliani, Gaston; Ohnenstetter, Daniel; Fallick, Anthony E.; Rakotosamizanany, Saholy; Andriamamonjy, Alfred; Ralantoarison, Théogène; Razanatseheno, Madison; Offant, Yohann; Garnier, Virginie; et al. (2008) Gem corundum deposits of Madagascar: A review. Ore Geology Reviews, 34 (1-2). 134-154 doi:10.1016/j.oregeorev.2007.05.001
 
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