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
Gangdalstjern mine, Solberg iron mines, Holt, Tvedestrand, Agder, Norway


Locality type:Mine
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 Gangdalstjern mine, Solberg iron mines, Holt, Tvedestrand, Agder, Norway
Data Identifiers
Mindat Occurrence Record ID:1622904
Long-form Identifier:1:3:1622904:0
GUID (UUID V4):0
Nearest other occurrences of Biotite
1.3km (0.8 miles) ⓘNordre Fiane Iron Mine, Solberg iron mines, Holt, Tvedestrand, Agder, Norway
1.3km (0.8 miles) ⓘJensen's Feldspar Quarry, Holt, Tvedestrand, Agder, Norway
4.5km (2.8 miles) ⓘFjeld Quarry (Fjellvand Quarry), Austre Moland, Arendal, Agder, Norway
4.8km (3.0 miles) ⓘGrasås Feldspar Quarry, Austre Moland, Arendal, Agder, Norway
5.8km (3.6 miles) ⓘMidtbø (Midbø), Tvedestrand, Agder, Norway
6.1km (3.8 miles) ⓘVåland Mine, Holt, Tvedestrand, Agder, Norway
6.4km (4.0 miles) ⓘØsterådalen, Østerå, Tvedestrand, Agder, Norway
8.0km (4.9 miles) ⓘSolbutjernane, Tvedestrand, Agder, Norway
9.2km (5.7 miles) ⓘSunde bridge, Snaresund, Tvedestrand, Agder, Norway
10.1km (6.3 miles) ⓘHauglandsvatnet, Vegårshei, Agder, Norway
References
(2001) Deposit Area 914 - 011. Solberg. The Ore Database, Geological Survey of Norway.
 
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