"The Mystery of Lyle and Louise"

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

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

White, mature, friable.

Gray to brown mudstone with abundant silt.

Gray to buff, with numerous ooliths and fossil fragments.

Brownish black, intermediate stage between peat and bituminous coal.

Black, soft; most widely mined.

Light gray, fine small clasts.

Dense and massive.

Hematite-cemented quartz; orthoquartzite.