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Sedimentary rock

Banded iron formation

Mostly Precambrian rocks of alternating dark iron-oxide layers (magnetite and hematite) and chert stained red by hematite; a common iron ore. Likely linked to low-oxygen oceans; the exact mechanism is debated.

Banded iron formation, about 2.1 billion years old
Banded iron formation, about 2.1 billion years old. Andre Karwath (2005), CC BY-SA. Source

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Other sedimentary rocks

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

Sources

Panchuk, Physical Geology 9.2: Chemical and Biochemical Sedimentary Rocks · Rygel & Quinton, Sedimentary Geology 7.2: Siliceous Sedimentary Rocks