"The Mystery of Lyle and Louise"

Lustrous, black 'hard coal'.

Shiny black volcanic glass showing conchoidal fracture and some spherulites.

Brownish black, intermediate stage between peat and bituminous coal.

Unpolished metamorphic rock with silky lusture, red-brown colour, and clear parallel intergrown quartz crystals.

Chlorite-mica with perfect slaty cleavage.

Brownish gray, translucent.

Coarse, 'salt and pepper': dark pyroxene and light andesine. Provides perfect representation of an intermediate igneous rock.

Yellow to orange crystal with a glassy luster and smooth, often transparent appearance.

Gray to white, coarse crystalline, carbonate rock.

Pure translucent to white, rhombic cleavages, Mohs’ hardness of 3.