Monomineralic rocks are rocks that are composed of only one mineral.
Examples of Monomineralic Rock
Monomineralic igneous rocks are dunite (more than 90% olivine) and anorthosite (more than 90% plagioclase feldspar).
Common monomineralic metamorphic rocks are marble and quartzite although they do not need necessarily to be monomineralic. Similar is the situation with their sedimentary protoliths – limestone and sandstone which may be very pure.