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
Grasås Feldspar Quarry, Austre Moland, Arendal, Agder, Norway


Locality type:Pegmatite
Classification
Species:'Biotite' (not an IMA approved species)
Formula:K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Grasås Feldspar Quarry, Austre Moland, Arendal, Agder, Norway
Data Identifiers
Mindat Occurrence Record ID:1982507
Long-form Identifier:1:3:1982507:6
GUID (UUID V4):0
Nearest other occurrences of Biotite
0.9km (0.6 miles) ⓘFjeld Quarry (Fjellvand Quarry), Austre Moland, Arendal, Agder, Norway
4.0km (2.5 miles) ⓘVåland Mine, Holt, Tvedestrand, Agder, Norway
4.5km (2.8 miles) ⓘJensen's Feldspar Quarry, Holt, Tvedestrand, Agder, Norway
4.8km (3.0 miles) ⓘGangdalstjern mine, Solberg iron mines, Holt, Tvedestrand, Agder, Norway
5.8km (3.6 miles) ⓘSeljeåsen Quartz Prospect, Seljåsen, Lyngrott, Froland, Agder, Norway
6.0km (3.8 miles) ⓘNordre Fiane Iron Mine, Solberg iron mines, Holt, Tvedestrand, Agder, Norway
6.6km (4.1 miles) ⓘÅrgruven Iron Mine, Lyngrott Mining Field, Lyngrott, Froland, Agder, Norway
7.0km (4.3 miles) ⓘGloserheia, Froland, Agder, Norway
9.1km (5.7 miles) ⓘSeljeåsen Nickel Prospect, Lyngrott, Froland, Agder, Norway
9.6km (6.0 miles) ⓘGarta Feldspar Quarry, Stokken, Arendal, Agder, Norway
References
Folvik, Jorun (1977) Weekendtur i Pinsen 1977. OG-Nytt. Medlemsblad for Oslo og omegn Geologiforening [Membership magazine for the Oslo Geology Association], p.7-9.
 
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