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Biotite from
Granitberg Complex, ǃNamiǂNûs Constituency, ǁKaras Region, Namibia


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:130 ± 2 Ma
Minimum recorded age:130 ± 2 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
1130 ± 2 MaEarly/Lower Cretaceous - K-Ar
Sample references:
1 -
Marsh, J. S. (1975) The Luderitz alkaline province, South West Africa. II. Metasomatism and assimilation in the contact aureole of the Granitberg foyaite complex. Transactions of the Geological Society of South Africa, 78. 225-233 doi:10.10520/EJC-1ac87e579d
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Granitberg Complex, ǃNamiǂNûs Constituency, ǁKaras Region, Namibia
Data Identifiers
Mindat Occurrence Record ID:1432663
Long-form Identifier:1:3:1432663:1
GUID (UUID V4):0
Nearest other occurrences of Biotite
30.2km (18.8 miles) ⓘDrachenberg Complex, ǃNamiǂNûs Constituency, ǁKaras Region, Namibia
36.1km (22.4 miles) ⓘPomona Complex, ǃNamiǂNûs Constituency, ǁKaras Region, Namibia
46.4km (28.9 miles) ⓘTefelskuppe Hills, ǃNamiǂNûs Constituency, ǁKaras Region, Namibia
75.4km (46.9 miles) ⓘKieshöhe carbonatite, ǃNamiǂNûs Constituency, ǁKaras Region, Namibia
75.6km (47.0 miles) ⓘChamais Plug, ǃNamiǂNûs Constituency, ǁKaras Region, Namibia
77.7km (48.3 miles) ⓘKeishohe carbonatites, ǃNamiǂNûs Constituency, ǁKaras Region, Namibia
83.5km (51.9 miles) ⓘRoter Kamm Crater, ǃNamiǂNûs Constituency, ǁKaras Region, Namibia
94.2km (58.5 miles) ⓘDicker Willem (Dicker Wilhelm; Garubberg), ǃNamiǂNûs Constituency, ǁKaras Region, Namibia
References
 
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