Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Opal from
Fougères Forest, Fougères, Fougères-Vitré, Ille-et-Vilaine, Brittany, France


Locality type:Forest
Classification
Species:Opal
Formula:SiO2 · nH2O
Comments:A discovery made in the twentieth century by Mr.Bouffort (pharmacist).
Pieces (rarely centimeter) of milky opal in granite (sometimes opalescent orange).
Colour:white, colorless
Quality for species:Rock forming mineral/non-crystalline/little interest for collectors.(##)
Abundance at site:Very Rare
Confirmation
Validity:Confirmed
Confirmation Methods:Visually Identified
Data
Mineral Data:Click here to view Opal data
Locality Data:Click here to view Fougères Forest, Fougères, Fougères-Vitré, Ille-et-Vilaine, Brittany, France
Data Identifiers
Mindat Occurrence Record ID:929589
Long-form Identifier:1:3:929589:6
GUID (UUID V4):0
Nearest other occurrences of Opal
38.4km (23.8 miles) ⓘLa Lucette mine, Le Genest-Saint-Isle, Laval, Mayenne, Pays de la Loire, France
43.6km (27.1 miles) ⓘLGV construction site (railroad), Le Pertre, Fougères-Vitré, Ille-et-Vilaine, Brittany, France
References
John BRUNET collection
 
and/or  
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