Browse Items (1651 total)

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Mottled lithology of the Muav Limestone.

Both thin section images were taken at a 400x magnification.

Limestone containing fossils of the alga, Girvanella.

Both thin section images were taken at a 400x magnification.

Hand Sample: Porphyritic latite with medium-to-coarse-grained subhedral plagioclase phenocrysts in a brown-black groundmass. Thin black veins present with green margin of contact on either side.

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Coarse grained sample from the Concord Granite. Thin section contains plagioclase, potassium feldspar, quartz, and muscovite. Hand sample is a coarse granite with quartz, feldspars, and muscovite.

Extremely coarse-grained muscovite schist. Large garnets visible in hand sample. Sillimanite is not recognizable in hand sample, however.

The thin section shows muscovite (with minor sillimanite) in a large band, biotite, staurolite, and…

Nepheline syenite that outcrops on west side of trail at about 9200 ft. on east side line of section.