"pathway PLASTICS, INC."

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

Lustrous, black 'hard coal'.

Small, rounded pebbles and tightly cemented granules.

Brown, fluorescent crystals intergrown in dolomite rock.

Brown, earthy, massive; used for yellow pigment.

Gray to white, coarse crystalline, carbonate rock.

Classic, dark; from the Columbia Plateau.

Gray, fine-grained, massive contact rock.

Fine to medium-grained with biotite.

Gray to buff, with numerous ooliths and fossil fragments.

Clear, pure cleavages, Mohs’ hardness of 2.

Silvery, paragranite and muscovite-rich with medium garnet crystals.

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

White, fibrous, silky luster.

Buff, coarse, crystalline “Austin Marble” with shell casts and molds.

Pure, bright yellow, Frasch sulfur.