# 5.9: A3 Schist

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## Outcrop and Hand Sample Photos and Videos

Click on the image to enlarge.

These outcrops are only a couple hundred meters down the road from the A3 amphibolite. The schist shows distinctive foliation in outcrop.

The hand sample shows the complex foliation in more detail. Pause the video when I show the side of the rock cut by a rock saw.

## Thin Section Photos and Videos

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

Hornblende (green-brown in ppl, yellow-orange-blue in xpl), garnet, qtz, plagioclase.

Entire thin section scan. 1st = ppl; 2nd = xpl.

This thin section is super interesting! Especially for thinking about deformation events. It was made from the cut side of the hand sample shown in the YouTube video above.

This page titled 5.9: A3 Schist is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Elizabeth Johnson and Juhong Christie Liu (Virtual Library of Virginia) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.