Definition of "Qtz"

The Phe + Qtz symplectite, grown preferentially along the planar perthitic exsolution lamellae, indicates that the albite exsolution (i.e., a first retrogression) occurred before the eclogite-facies metamorphism […] .

2017, J. Theo Kloprogge, Robert Lavinsky, “Introduction: Geological Examples”, in Photo Atlas of Mineral Pseudomorphism, Amsterdam: Elsevier, page 88