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Phengite from
Pratoluogo, Venasca, Cuneo Province, Piedmont, Italy


Locality type:Occurrence
Classification
Species:Muscovite var: Phengite
Formula:KAl1.5(Mg,Fe)0.5(Al0.5Si3.5O10)(OH)2
Comments:Two 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
Associated Minerals Based on Photo Data:
Pyrope1
Magnesiostaurolite1
Data
Mineral Data:Click here to view Phengite data
Locality Data:Click here to view Pratoluogo, Venasca, Cuneo Province, Piedmont, Italy
Data Identifiers
Mindat Occurrence Record ID:542957
Long-form Identifier:1:3:542957:8
GUID (UUID V4):0
Nearest other occurrences of Phengite
9.0km (5.6 miles) ⓘGilba Valley, Brossasco, Cuneo Province, Piedmont, Italy
19.4km (12.1 miles) ⓘVerné, Sampeyre, Cuneo Province, Piedmont, Italy
19.9km (12.4 miles) ⓘPunta Rasciassa, Oncino, Cuneo Province, Piedmont, Italy
20.6km (12.8 miles) ⓘCastello Oddino quarries, Barge, Cuneo Province, Piedmont, Italy
21.0km (13.0 miles) ⓘCion quarries, Barge, Cuneo Province, Piedmont, Italy
21.4km (13.3 miles) ⓘPerrone quarries, Barge, Cuneo Province, Piedmont, Italy
22.1km (13.8 miles) ⓘRocca del Toro Quarry, Montoso Quarries, Bagnolo Piemonte, Cuneo Province, Piedmont, Italy
22.2km (13.8 miles) ⓘBalma Oro Quarry, Montoso Quarries, Bagnolo Piemonte, Cuneo Province, Piedmont, Italy
22.3km (13.9 miles) ⓘPravallino Quarry, Montoso Quarries, Bagnolo Piemonte, Cuneo Province, Piedmont, Italy
22.5km (14.0 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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