(Massiccio Dora Maira, Cuneo, Piemonte, Italia)
Very high pressure metamorphism of Mg-rich pelites, at depths over 100 km, have created this very unusual pyrope-coesite-quartzite, now exposed in the Western Alps. Famous for its (nearly) colorless, very pure pyrope (over 95% pyrope molecule) as crude crystals up to coconut size. High-pressure phases like ellenbergerite and coesite are preserved only as inclusions in the pyrope, not in the surrounding matrix.
The main composition of the quartzite is: quartz, phengite, talc, kyanite, pyrope.
Ref.:
Hermann, J. (2003) Experimental evidence for diamond-facies metamorphism in the Dora-Maira massif. Lithos 70: 163-182.
Mineral list contains entries from the region specified including sub-localitiesMineral List:111 entries listed. 44 valid minerals. 5 type localities (valid minerals).
Localities in this Region: The above list contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database!
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