Typical graphic granite forms about one-third of the containing pegmatite dikes in the Romona district, California. A quartz-perthite ratio of about 1:3 characterizes this graphic granite, and the microcline-albite ratio within the perthite is about 2:1. The quartz rods in a single specimen of graphic granite generally have a single crystallographic orientation, but this orientation is different for different specimens and is not consonant with any crystallographic law. Moreover, the c axis of quartz is commonly not the axis of elongation of the rod, nor does the c axis have a systematic angular relation to the walls of the pegmatite dike. Successive surfaces cut in a block of graphic granite reveal many interconnections of the quartz rods. The features of the Ramona graphic granite and its nature of occurrence suggest that the quartz and feldspar crystallized simultaneously, probably from a vapor phase.

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