Sandstone (Sedimentary)
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In plain terms
Sandstone is sand turned to rock—its grains and cement tell you where it came from and how it was deposited.
What to look for
- Sand-sized grains you can often feel or see
- Sorting (uniform vs mixed sizes) and rounding (angular vs rounded)
- Cement type (silica, calcite, iron oxides) affecting color and durability
- Bedding and cross-bedding
Key takeaways
- Grain size and sorting reflect transport energy.
- Cross-beds can indicate flow direction.
- Cement controls strength and weathering.
- Iron-rich cement often produces red/brown tones.
- Context helps separate sandstone from similar-looking quartzite.