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Phengite from
Gilba Valley, Brossasco, Cuneo Province, Piedmont, Italy


03952130017362830545477.jpg
Phengite

Gilba Valley, Brossasco, Cuneo Province, Piedmont, Italy
03952130017362830545477.jpg
Phengite

Gilba Valley, Brossasco, Cuneo Province, Piedmont, Italy
06185440017362306023475.jpg
Phengite

Gilba Valley, Brossasco, Cuneo Province, Piedmont, Italy
Locality type:Valley
Classification
Species:Muscovite var: Phengite
Formula:KAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2
Comments:Different types of phengite are observed in the host rock and as inclusions in pyrope crystals.
The white mica, occurring as inclusions in pyrope, is a Fe-free phengite ascribable to an intermediate member of the solid-solution series aluminoceladonite-muscovite. A typical composition, represented by the empirical formula K0.93Na0.02(Al1.41Mg0.59)(Si3.60Al0.40O10)(OH)2, is reported by Chukanov (2014).
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Phengite data
Locality Data:Click here to view Gilba Valley, Brossasco, Cuneo Province, Piedmont, Italy
Data Identifiers
Mindat Occurrence Record ID:574814
Long-form Identifier:1:3:574814:3
GUID (UUID V4):0
Nearest other occurrences of Phengite
9.0km (5.6 miles) ⓘPratoluogo, Venasca, Cuneo Province, Piedmont, Italy
10.9km (6.8 miles) ⓘVerné, Sampeyre, Cuneo Province, Piedmont, Italy
10.9km (6.8 miles) ⓘPunta Rasciassa, Oncino, Cuneo Province, Piedmont, Italy
13.9km (8.6 miles) ⓘCastello Oddino quarries, Barge, Cuneo Province, Piedmont, Italy
14.5km (9.0 miles) ⓘCion quarries, Barge, Cuneo Province, Piedmont, Italy
14.5km (9.0 miles) ⓘPerrone quarries, Barge, Cuneo Province, Piedmont, Italy
15.6km (9.7 miles) ⓘMorelli outcrop, Elva, Cuneo Province, Piedmont, Italy
15.6km (9.7 miles) ⓘRocca del Toro Quarry, Montoso Quarries, Bagnolo Piemonte, Cuneo Province, Piedmont, Italy
15.6km (9.7 miles) ⓘBalma Oro Quarry, Montoso Quarries, Bagnolo Piemonte, Cuneo Province, Piedmont, Italy
16.1km (10.0 miles) ⓘCassetta Quarry, Montoso Quarries, Bagnolo Piemonte, Cuneo Province, Piedmont, Italy
References
Piccoli, G.C., Maletto, G., Bosio, P., Lombardo, B. (2007) Minerali del Piemonte e della Valle d'Aosta - Associazione Amici del Museo "F. Eusebio" Alba.
Chukanov, Nikita V. (2014) Springer Geochemistry/Mineralogy - Infrared spectra of mineral species. Springer Netherlands. doi:10.1007/978-94-007-7128-4p.438
 
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