"WardsSci000452"

Black, soft; most widely mined.

Small, rounded pebbles and tightly cemented granules.

Well-cemented, medium-grained orthoquartzite.

Gray and poorly sorted, with a gritty texture.

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

Useful for weathering and erosion, soil formation, porosity and permeability, or other general earth science labs.

Light gray, earthy.

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

Brownish gray, kerogen-rich; commercial oil source.

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