Microgranite is a medium-grained intrusive igneous rock. It contains crystals, smaller than grains of rice, which are interlocking and randomly oriented. It is pale grey and can sometimes be pinkish in colour.
It contains a number of minerals, mostly feldspars, which are pale grey or pinkish, and quartz, which is grey or white. It also contains small specs of mafic (dark coloured) minerals.
How was it formed?
Microgranite is the medium-grained equivalent of granite. The crystals are slightly smaller than granite indicating that the magma cooled more quickly. It usually occurs in smaller intrusions than granite. Microgranite forms from magma that contains a lot of quartz (silica).
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