Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Biotite from
Kalkfeld Complex, Kalkfeld, Otjiwarongo Constituency, Otjozondjupa 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:172.8 Ma
Minimum recorded age:153.6 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
1172.8 to 153.6 MaJurassic - K-Ar
Sample references:
1 -
ZIEGLER, U. F. (1992). Preliminary results of geochemistry, Sm-Nd and Rb-Sr studies of post-Karoo carbonatite complexes in Southern Africa. Schweizerische mineralogische und petrographische Mitteilungen, 72(1), 141-148.
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Kalkfeld Complex, Kalkfeld, Otjiwarongo Constituency, Otjozondjupa Region, Namibia
Data Identifiers
Mindat Occurrence Record ID:715111
Long-form Identifier:1:3:715111:8
GUID (UUID V4):0
Nearest other occurrences of Biotite
13.4km (8.4 miles) ⓘKameelburg Complex, Kalkfeld, Otjiwarongo Constituency, Otjozondjupa Region, Namibia
84.4km (52.5 miles) ⓘOkenyenya Complex, Dâures Constituency, Erongo Region, Namibia
References
 
and/or  
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