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Biotite from
Rocher du Crapaud beach alluvials, Lanildut, 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 Rocher du Crapaud beach alluvials, Lanildut, Brest, Finistère, Brittany, France
Data Identifiers
Mindat Occurrence Record ID:442487
Long-form Identifier:1:3:442487:1
GUID (UUID V4):0
Nearest other occurrences of Biotite
6.2km (3.8 miles) ⓘRuscumunoc beach alluvial deposits, Ruscumunoc, Plouarzel, Brest, Finistère, Brittany, France
11.2km (7.0 miles) ⓘBlancs Sablons beach alluvials, Le Conquet, Brest, Finistère, Brittany, France
14.9km (9.3 miles) ⓘTrégana beach alluvials, Trégana, Locmaria-Plouzané, Brest, Finistère, Brittany, France
16.4km (10.2 miles) ⓘGuélet ar C'hoat, Plouguin, Brest, Finistère, Brittany, France
21.2km (13.2 miles) ⓘWrac'h island, Lilia, Plouguerneau, Brest, Finistère, Brittany, France
24.3km (15.1 miles) ⓘPenn ar Roc'h - Porz an Ejen area, Ushant, Brest, Finistère, Brittany, France
29.2km (18.2 miles) ⓘToullouarn quarry, Guissény, Brest, Finistère, Brittany, France
34.3km (21.3 miles) ⓘSaint-Egarec beach alluvials, Kerlouan, Brest, Finistère, Brittany, France
45.4km (28.2 miles) ⓘPointe du Van, Cléden-Cap-Sizun, Quimper, Finistère, Brittany, France
47.9km (29.8 miles) ⓘPointe du Raz, Plogoff, 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. 127 à 129.
 
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