5.7: A1 B2 Schist

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Outcrop and Hand Sample Photos and Videos

This outcrop is on a busy road. The schist is coated in a dark later of pollution from car exhaust, making it look black on the outcrop. A fresh surface reveals a shiny silver schist.

The staurolite is the large orange porphyroblasts in the hand sample. Dark minerals are biotite. Much of the rock is muscovite, some quartz, a little plagioclase. Kyanite is rumored to be present. Tiny garnets are hardly visible in hand sample.

Thin Section Photos and Videos

1st = plane polarized light; 2nd = cross-polarized light.

Area 1

Biotite (brown in ppl) and staurolite (yellow in ppl, top left) porphyroblasts. High-relief euhedral mineral is garnet. Qtz and muscovite are also present.