L324 - Sandstone, feldspathic arenite

Hand Specimen

Reddish brown rock made up of pinkish feldspar, colourless quartz, and some dark grey grains. Medium to coarse sand. Moderately rounded. Fairly well sorted. 
Contains <15 vol% clay, so this is an arenite. 
No fizzing with acid, so does not contain significant carbonate.

Quartz (~65%) 
- Includes fresh quartz grains with undulose extinction, quartzite grains with internal sutures, and quartz vein material. Some quartz grains have opaque rims.

Feldspar (~35%) 
- Mainly microcline, some plagioclase. Some microperthite texture and decomposition to clays.

All grains are moderately rounded and fairly well sorted. The rock is well compacted. A thin film of cement mainly hematite and clay coats the grains.

This rock contains too much feldspar, and the grains are not sufficiently well rounded nor well sorted to have been deposited in an aeolian environment. The sediments were deposited in an aqueous environment.

sandstone
feldspathic arenite