"gel box"

4 pounds of limestone chips supplied in a box.

Indicative of Various Sedimentary Formation Processes

Light gray, earthy.

Brownish gray, kerogen-rich; commercial oil source.

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

Well-cemented, medium-grained orthoquartzite.

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

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

Dense and massive.

Gray to buff, with numerous ooliths and fossil fragments.