monzonite

An igneous rock composed chiefly of plagioclase feldspar and orthoclase, with small amounts of other minerals.

In petrography, a phaneric igneous rock intermediate in composition between syenite and diorite, that is, composed of alkali feldspar, usually orthoclase, and lime-soda feldspar, andesin or labradorite, in equal or nearly equal proportions, with subordinate amounts of hornblende, pyroxene, or mica, rarely olivin, and minor constituents. There may be a variable amount of quartz: when it is present in considerable amount the rock is quartz-monzonite or granodiorite.

An intrusive igneous rock composed mostly of plagioclase and orthoclase