[Rockhounds] Garnet & Kyanite

[Carolyn Reynard]

Jim,   

Kyanite forms at a higher pressure and temperature than garnet, so usually they are not together. There are exceptions I have a specimen from Russia that has both. I believe that would indicate my Russian specimen is right on the boundary ( isograd) between the two. (adjacent metamorphic zones on a map are separated by isograds or line of equal grade.)

 Not sure about the alteration of kyanite to mica, but I do know cordierite alters to mica, so there is a good possibility. Kyanite is often found  mica schist.

Carolyn Reynard



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