Graphic granite is an igneous rock with a very distinctive texture of intergrown crystals of quartz and alkali feldspar. The rock is white or pink.
Figure 1. Two hand specimens (each about 4 inches tall) of graphic granite collected by the author from San Diego County, southern California. The scale in the image is in centimeters.
The intergrown crystals produce a texture that looks like ancient, angular cuneiform or hieroglyphic script. This disintictive texture is the result of simultaneous crystallization of quartz rods with the host feldspar crystals.
This kind of rock forms in granitic pegmatives during the simultaneous cooling and crystallization of molten magma saturated with both feldspar and quartz.
Graphic granite is found throughout the world at various locales (e.g., the Rocky Mountains, America).
The name is derived from the Latin grapus and the Greek gryphos---both words meaning to write.
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