"Microtomes and Microtome Assemblies"

Formalin Preserved

Formalin Preserved

Formalin preserved land snails. Available in jars or pails.

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

Utah

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

White and black bands of quartz, feldspar, and biotite; typical foliation.

Pink and gray bands, with biotite; shows good foliation.

Gray to brown mudstone with abundant silt.

Fightly cemented, medium-to-coarse quartz grains.

Black, soft; most widely mined.

Lustrous, black 'hard coal'.

Light gray, fine small clasts.

Dense and massive.

Hematite-cemented quartz; orthoquartzite.

Pure, large, transparent-to-translucent cleavages, Mohs’ hardness of 4.