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Opal from
Eiras quarry, Gondomil e Safins, Valença do Minho, Viana do Castelo, Portugal


07198300017362089043118.jpg
Opal-AN, etc.

Eiras quarry, Gondomil e Safins, Valença do Minho, Viana do Castelo, Portugal
07198300017362089043118.jpg
Opal-AN, etc.

Eiras quarry, Gondomil e Safins, Valença do Minho, Viana do Castelo, Portugal
07198300017362089043118.jpg
Opal-AN, etc.

Eiras quarry, Gondomil e Safins, Valença do Minho, Viana do Castelo, Portugal
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 Eiras quarry, Gondomil e Safins, Valença do Minho, Viana do Castelo, Portugal
Data Identifiers
Mindat Occurrence Record ID:994458
Long-form Identifier:1:3:994458:9
GUID (UUID V4):0
Nearest other occurrences of Opal
15.6km (9.7 miles) ⓘPorriño quarries, Porriño, Pontevedra, Galicia, Spain
19.1km (11.9 miles) ⓘCillarga Quarry, Ponteareas, Pontevedra, Galicia, Spain
References
Alves, Pedro (n.d.) Personal communication.
Nuno Afonso collection (XRD-analysed)
 
and/or  
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