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Micropegmatite Granite
Field Collector: Esper Signius Larsen Jr.
Place Collected:Near Corona, Corona Quadrangle, Southern California
Object number: ROC21693
DescriptionPink porphyritic, plutonic igneous rock with plagioclase phenocrysts up to 3 mm long in a matrix of intergrown quartz and K-feldspar. The porphyritic texture of this rock is unclear in hand sample. Mineral modes according to Larsen (1948) are 39% quarz, 35% perthite (K-feldspar), 22% plagioclase, 2% biotite, and 0.3% Fe-ore.
In Collection(s)