WSU Sample 1124

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This sample was collected from a quarry of the Little Cottonwood Stock which was also the source of the “granite” used to build the Salt Lake City Church of Jesus Christ of Latter Day Saints Templ and the Utah Capitol Building, among others. Clearly, the sample contains both whitish plagioclase and pale pinkish potassium feldspars as well as light gray glassy quartz. Other minerals include biotite, several grains that appear to be hornblende (?), and rare macroscopic titanite. Some of the k-spar grains are phenocrysts, so technically this is a phaneritic porphyry. The ratio of quartz to k-spar to plagioclase could make this sample a “granite” but Jensen (BYU PHD Dissertation, 2019), notes that the essential mineralogy clusters around the “triple point” between granite, granodiorite, and quartz monzonite. Which do you think this sample is?