"The Mystery of Lyle and Louise"

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

White, mature, friable.

1 pound of black sand packaged in a heat-sealed bag.

Gray to brown mudstone with abundant silt.

Black, soft; most widely mined.

Gray to buff, with numerous ooliths and fossil fragments.

Light gray, fine small clasts.

Dense and massive.

Hematite-cemented quartz; orthoquartzite.

Brownish black, intermediate stage between peat and bituminous coal.