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Bertrandite from
Gwernavalou Quarry, Trémargat, Guingamp, Côtes-d'Armor, Brittany, France


Locality type:Quarry
Classification
Species:Bertrandite
Formula:Be4(Si2O7)(OH)2
Habit:Pseudo-hexagonal prism
Colour:Colorless
Quality for species:Good crystals or rich for species - important (!)
Abundance at site:Rare
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Bertrandite data
Locality Data:Click here to view Gwernavalou Quarry, Trémargat, Guingamp, Côtes-d'Armor, Brittany, France
Data Identifiers
Mindat Occurrence Record ID:198791
Long-form Identifier:1:3:198791:1
GUID (UUID V4):0
Nearest other occurrences of Bertrandite
49.3km (30.7 miles) ⓘMénez Goaillou pegmatite quarries, Coray, Châteaulin, Finistère, Brittany, France
77.1km (47.9 miles) ⓘQuily quarry, Quily, Pontivy, Morbihan, Brittany, France
78.1km (48.5 miles) ⓘLa Villeder, Le Roc Saint-André, Pontivy, Morbihan, Brittany, France
References
Germain C., Guillou A. (1988), Le Cahier des Micromonteurs, n°3, 3-7
 
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