"WardsSci000452"

Buff-colored, coarse, detrital limestone, with cemented shell fragments.

Fine, common limestone; massive, and will fizzle with HCl.

Black, fissile; commonly with carbonized fossil plant impressions.

Dense and massive.

Earthy, porous calcareous tufa.

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Small, rounded pebbles and tightly cemented granules.

Hematite-cemented quartz; orthoquartzite.

Brownish black, intermediate stage between peat and bituminous coal.

White, mature, friable.

Gray to brown mudstone with abundant silt.

Typical green-gray, fissile, clay-rich.

Hardened natural cement of calcium carbonate that binds other material such as gravel, sand, clay, and silt.

Buff, coarse, crystalline “Austin Marble” with shell casts and molds.

Gray with line crinoid columnal fragments.

Red, medium, to coarse-grained iron oxide cement; shows hematite bands.