Phengite
| Phengite | |
|---|---|
Phengite
|
|
| General | |
| Category | Mica group |
|
Formula (repeating unit) |
K(AlMg)2(OH)2(SiAl)4O10 |
Phengite is a series name for dioctahedral micas of composition K(AlMg)2(OH)2(SiAl)4O10, similar to muscovite but with addition of magnesium. It is a non-IMA recognized mineral name representing the series between muscovite and celadonite.
The silica content of phengite has been proposed as a geobarometer for the metamorphism of low grade schists.
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