"WardsSci000452"

Compact Plant Fiber Masses.

Black, soft; most widely mined.

Well-cemented, medium-grained orthoquartzite.

Gray and poorly sorted, with a gritty texture.

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

Light gray, earthy.

Brownish gray, kerogen-rich; commercial oil source.

Massive sedimentary gypsum with a moh's hardness 2..

Gray to tan clastic rock made of silt sized particles.

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