Aplite

Aplite: intrusive and metamorphic rocks rich in silica (hypersilicic) with abundant Quartz and Feldspars, nearly or completely lacking mafic minerals. They generally form the neosome (light-colored areas with leucogranitic composition) of migmatites or represent acidic differentiations of magmas with varied compositions, or they fill dikes, veins, and apophyses. They have an automorphous structure (lacking an order of crystallization), also called aplitic, with a very fine grain size.

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