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Biotite from
Ruscumunoc beach alluvial deposits, Ruscumunoc, Plouarzel, Brest, Finistère, Brittany, France


Locality type:Alluvials
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 Ruscumunoc beach alluvial deposits, Ruscumunoc, Plouarzel, Brest, Finistère, Brittany, France
Data Identifiers
Mindat Occurrence Record ID:438798
Long-form Identifier:1:3:438798:5
GUID (UUID V4):0
Nearest other occurrences of Biotite
5.9km (3.6 miles) ⓘBlancs Sablons beach alluvials, Le Conquet, Brest, Finistère, Brittany, France
6.2km (3.8 miles) ⓘRocher du Crapaud beach alluvials, Lanildut, Brest, Finistère, Brittany, France
11.9km (7.4 miles) ⓘTrégana beach alluvials, Trégana, Locmaria-Plouzané, Brest, Finistère, Brittany, France
21.1km (13.1 miles) ⓘGuélet ar C'hoat, Plouguin, Brest, Finistère, Brittany, France
21.9km (13.6 miles) ⓘPenn ar Roc'h - Porz an Ejen area, Ushant, Brest, Finistère, Brittany, France
27.2km (16.9 miles) ⓘWrac'h island, Lilia, Plouguerneau, Brest, Finistère, Brittany, France
34.6km (21.5 miles) ⓘToullouarn quarry, Guissény, Brest, Finistère, Brittany, France
39.8km (24.7 miles) ⓘSaint-Egarec beach alluvials, Kerlouan, Brest, Finistère, Brittany, France
40.0km (24.9 miles) ⓘPointe du Van, Cléden-Cap-Sizun, Quimper, Finistère, Brittany, France
42.2km (26.2 miles) ⓘNerroth island, Sein Island, Quimper, Finistère, Brittany, France
References
Chauris L. (1982), A la recherche des placers littoraux : concentration de sables lourds sur les plages du Nord –Finistère (Massif Armoricain), 107ème congrès des sociétés savantes, Brest, sciences, fasc. III, p. 128.
 
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