Mineral: Spessartine glaucophane schist
Locality: Bagnes Valley, Wallis (Valais), Switzerland
Dimensions: FOV 5 cm.

Description: Another partial view of the polished surface with an interesting detail. Next to the green crystals you can see a white mineral showing evident cleavage, so it can't be quartz (quartz appears here as a massive frame of garnets). It might be albite (a mineral possible in this blueschist facies). Albite can hardly ever coexist with omphacite according to the metamorphic reaction albite < --- > jadeite + quartz As jadeite is an essential component of omphacite, the presence of albite discards the omphacite in a high degree. Anyway omphacite can coexist sometimes wiht retrograde albite to some extent.

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