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


07825700017271983745848.jpg
Opal-AN

Gwernavalou Quarry, Trémargat, Guingamp, Côtes-d'Armor, Brittany, France
08029290017370781157858.jpg
Opal-AN

Gwernavalou Quarry, Trémargat, Guingamp, Côtes-d'Armor, Brittany, France
07825700017271983745848.jpg
Opal-AN

Gwernavalou Quarry, Trémargat, Guingamp, Côtes-d'Armor, Brittany, France
08029290017370781157858.jpg
Opal-AN

Gwernavalou Quarry, Trémargat, Guingamp, Côtes-d'Armor, Brittany, France
07825700017271983745848.jpg
Opal-AN

Gwernavalou Quarry, Trémargat, Guingamp, Côtes-d'Armor, Brittany, France
00052070017369124171608.jpg
Opal-AN

Gwernavalou Quarry, Trémargat, Guingamp, Côtes-d'Armor, Brittany, France
Locality type:Quarry
Classification
Species:Opal
Formula:SiO2 · nH2O
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Opal data
Locality Data:Click here to view Gwernavalou Quarry, Trémargat, Guingamp, Côtes-d'Armor, Brittany, France
Data Identifiers
Mindat Occurrence Record ID:198805
Long-form Identifier:1:3:198805:5
GUID (UUID V4):0
Nearest other occurrences of Opal
35.5km (22.0 miles) ⓘQuistiav (Quistiave), Guern, Pontivy, Morbihan, Brittany, France
51.5km (32.0 miles) ⓘSaint-Lubin, Saint-Brieuc, Côtes-d'Armor, Brittany, France
References
Germain C., Guillou A. (1988), Le Cahier des Micromonteurs, n°3, 3-7
 
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