Kuna Crest Granodiorite

Kuna Crest Granodiorite (also called Granodiorite of Glen Aulin), is found, in Yosemite National Park, United States. The granodiorite forms part of the Tuolumne Intrusive Suite (aka Tuolumne Batholith), one of the four major intrusive suites within the Sierra Nevada. Of the Tuolumne Intrusive Suite, it is the oldest and darkest rock.

Kuna Crest granodiorite forms most of the outer part of the Tuolumne Intrusive Suite, on the edges.

The word Kuna derives from a Numic word meaning "fire,". The rocks on Kuna Peak can be a red color and Kuna Peak is the highest point on Kuna Crest. Kuna Crest granodiorite was first identified on Kuna Crest, from which Kuna Peak rises.

Kuna Crest Granodiorite makes up most of the outer part of the Tuolumne Intrusive Suite. Of the Tuolumne Intrusive Suite, it is the most melanocratic of the granodiorites containing many mafic microgranular enclaves. It is fine- to medium-grained (0.1–4 mm). The mafic minerals are generally oriented and define a foliation.

Plagioclase is its most abundant mineral and is generally in euhedral crystals with rare inclusions. Thus plagioclase is viewed the first phase to crystallize from the magma.

The cores of some crystals are irregularly shaped, and have more sodium than outer parts. There is evidence that magma producing Kuna Crest Granodiorite mixed with other magmas.

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