Graphic granite is a type of granite that lacks mica and is chiefly composed of quartz and feldspar. The crystals in the rock are arranged in such a way that in transverse sections they appear similar to oriental characters or runes, a fact that is responsible for the rock’s alternate moniker, runite.

When the unusual crystal structure of graphic granite occurs on a microscopic scale, the rock is usually referred to as micropegmatite, though it is also occasionally known by the name of microgranite. This structure is specifically comprised of patches of quartz crystals in parallel orientation, which usually appear triangular in cross section, and quartz-feldspar interfaces that are planar. The remarkable angularity and parallelism of the crystals of quartz are generally believed to be a reaction to the conditions present during their growth.

Micropegmatite is the dominant material that comprises granophyres, fine-grained granite porphyries that consist of irregular intergrowths of quartz and feldspar imbedded in a groundmass. However, the rock may also often be found among common granites and the fine-grained igneous rocks called diabases. Within the latter, micropegmatite is often interstitial, appearing as veins, seams, or aggregates.

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