Sedimentary rock

Limestone

Made of calcite and aragonite, and by far the most common biochemical sedimentary rock. It fizzes vigorously in dilute hydrochloric acid. Classify it with Folk (grains + spar or micrite) or Dunham (mud vs. grain support).

In thin section

See carbonate components and fossils in thin section.

**Mollusc-rich limestone, foraminifera-rich sediment and ooids.** Steven Earle (2015), CC BY 4.0; ooids Mark Wilson (2010), public domain. Source

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More photos and thin sections

Carbonate classification on CratonLab

Other sedimentary rocks

Conglomerate and breccia · Quartz arenite · Arkose · Lithic arenite · Wacke (greywacke) · Mudrocks: shale, mudstone, siltstone, claystone · Chalk · Coquina · Oolite · Travertine and tufa · Dolostone · Chert · Diatomite · Radiolarite · Evaporites: rock salt and gypsum · Banded iron formation · Coal: peat to anthracite · Oil shale

Sources

Panchuk, Physical Geology 9.2: Chemical and Biochemical Sedimentary Rocks · Wikipedia: Limestone · Rygel & Quinton, Sedimentary Geology 6.3: Carbonate Components and Classification