Noun
A mineral of the feldspar group, like orthoclase or common feldspar in composition, but triclinic in form.
Source: Webster's dictionaryFeldspar (Amazonite) Perthite is either microcline or orthoclase with thin lamellae of exsolved albite. Source: Internet
In the acid rocks the common feldspars are orthoclase, perthite, microcline, and oligoclase—all having much silica and alkalis. Source: Internet
Microcline may be clear, white, pale-yellow, brick-red, or green; it is generally characterized by cross-hatch twinning that forms as a result of the transformation of monoclinic orthoclase into triclinic microcline. Source: Internet