Graphic texture is commonly created by exsolution and devitrification and immiscibility processes in igneous rocks. It is called 'graphic' because the exsolved or devitrified minerals form lines and shapes which are reminiscent of writing.
Graphic granite is a leucocratic granitic rock consisting of alkali feldspar with exsolved quartz typically forming a distinctive repetitive pattern sometimes resembling cuneiform or Arabic writing. Experiments have shown that graphic granite texture is derived from large single crystals of quartz and feldspar interleaving to create the cuneiform illusion.Fen, Philip M., 1986, On the Origin of Graphic Granite, American Mineralogist, Vol. 71, pp. 325-330
Exsolved magnetite has graphic texture, as do some exsolution textures of pyroxene, pyrite feldspar and rarely other minerals.
See also List of rock textures
Peperite
References
External links Gallery of graphic granites