Definition of quartz monzonite
A medium- to coarse-grained, holocrystalline, acidic plutonic rock containing major plagioclase, orthoclase, and quartz, with minor biotite and/or hornblende, and trace to accessory apatite, zircon, and opaque oxides. Similar to granite but with subequal amounts of plagioclase and orthoclase. The plagiocase/ K feldspar ratio ranges from 1/3 to 2/3; with increasing orthoclase it grades into granite, with increasing plagioclase, into granodiorite.
IUGS preferred synonym of: adamellite
IUGS preferred synonym of: adamellite