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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Illite from
Le Semnon, Martigné-Ferchaud, Fougères-Vitré, Ille-et-Vilaine, Brittany, France


Locality type:Mine
Classification
Species:Muscovite var: Illite
Formula:K0.65Al2.0[Al0.65Si3.35O10](OH)2
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Illite data
Locality Data:Click here to view Le Semnon, Martigné-Ferchaud, Fougères-Vitré, Ille-et-Vilaine, Brittany, France
Data Identifiers
Mindat Occurrence Record ID:1232913
Long-form Identifier:1:3:1232913:9
GUID (UUID V4):0
Nearest other occurrences of Illite
99.2km (61.6 miles) ⓘRouez mine, Tennie, Mamers, Sarthe, Pays de la Loire, France
References
Pochon, Anthony; Gloaguen, Eric; Branquet, Yannick; Poujol, Marc; Ruffet, Gilles; Boiron, Marie-Christine; Boulvais, Philippe; Gumiaux, Charles; Cagnard, Florence; Gouazou, Fanny; et al. (2018) Variscan Sb-Au mineralization in Central Brittany (France): A new metallogenic model derived from the Le Semnon district. Ore Geology Reviews, 97. 109-142 doi:10.1016/j.oregeorev.2018.04.016
 
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