"gel box"

Fightly cemented, medium-to-coarse quartz grains.

Gray to white, coarse crystalline, carbonate rock.

Classic, dark; from the Columbia Plateau.

Glassy; most specimens float in water.

Gray-to-brown basaltic, with over 50% vesicles.

Pink/gray coarse carbonate rock.

Light gray, earthy.

Chlorite-mica with perfect slaty cleavage.

Slaty cleavage; contains hematite.

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