"gel box"

Gray to white, coarse crystalline, carbonate rock.

Classic, dark; from the Columbia Plateau.

Light gray, earthy.

Chlorite-mica with perfect slaty cleavage.

Pink/gray coarse carbonate rock.

Gray, fine, friable, with abundant small sanidine crystal fragments.

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

Brownish gray, kerogen-rich; commercial oil source.

Light gray, with flow structure.

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