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Biotite from
Nejoio Complex, Camacuio, Namibe Province, Angola


Locality type:Volcanic 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:104.3 ± 0.8 Ma
Minimum recorded age:104.3 ± 0.8 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
1104.3 ± 0.8 MaEarly/Lower Cretaceous - Rb-Sr
Sample references:
1 -
Allsopp, H. L., & Hargraves, R. B. (1985). Rb-Sr ages and palaeomagnetic data for some Angolan alkaline intrusives. Transactions of the Geological Society of South Africa, 88(2), 295-299.
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Nejoio Complex, Camacuio, Namibe Province, Angola
Data Identifiers
Mindat Occurrence Record ID:1421650
Long-form Identifier:1:3:1421650:1
GUID (UUID V4):0
Nearest other occurrences of Biotite
19.0km (11.8 miles) ⓘChicacimo occurrence, Camacuio, Namibe Province, Angola
32.1km (20.0 miles) ⓘLutala Complex, Camacuio, Namibe Province, Angola
41.1km (25.5 miles) ⓘMacula occurrence, Benguela Province, Angola
72.2km (44.8 miles) ⓘMount Tchivira, Quilengues, Huíla Province, Angola
75.0km (46.6 miles) ⓘMount Bonga, Quilengues, Huíla Province, Angola
References
Rodrigues, B. 1978. Processos de evolucao magmatica no complexo alcalino do Nejoio. Boletim do Museo e Laboratorio Mineralogico e Geologico da Faculdade de Ciencias, Universidade de Lisboa, 15.
Allsopp, H. L., & Hargraves, R. B. (1985). Rb-Sr ages and palaeomagnetic data for some Angolan alkaline intrusives. Transactions of the Geological Society of South Africa, 88(2), 295-299.
Borst, Anouk M, Finch, Adrian A, Siegfried, Peter Roy, Bambi, Aurora (2023) Mixing, mingling and metasomatism: Late-stage HFSE mobility and carbothermal alteration in the Nejoio alkaline silicate complex, Angola. Goldschmidt 2023 Conference, GOLDSCHMIDT.
 
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