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Biotite from
Tundulu Ring Complex, Phalombe, Southern Region, Malawi


Locality type:Complex
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:140 Ma
Minimum recorded age:126 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
1140 to 126 MaEarly/Lower Cretaceous - K-Ar
2133 Âą 7 MaEarly/Lower Cretaceous - K-Ar
Sample references:
1 -
Orris, Greta J.; Grauch, Richard I.; Grauch, R. I.; Orris, G. J. (2002) Rare Earth Element Mines, Deposits, and Occurrences. Open-File Report 2002-189 doi:10.3133/ofr02189
2 -
SNELLING, N. J. (1965) Age Determinations on Three African Carbonatites. Nature, 205 (4970). 491 doi:10.1038/205491a0
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Tundulu Ring Complex, Phalombe, Southern Region, Malawi
Data Identifiers
Mindat Occurrence Record ID:715058
Long-form Identifier:1:3:715058:6
GUID (UUID V4):0
References
 
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