Quartz after coesite  

The region of coarser-grained quartz in the upper center portion of this photomicrograph was probably originally occopied by coesite, the high-pressure polymorph of quartz. Metamorphic rocks from the Dora Maira Massif show other evidence of being exhumed from EXTREMELY deep levels in thickened crust.

UNC sample


(K. Stewart)

Rock type

qtz-ky-gt-musc schist


Dora Maira Massif, Parigi, Italy