"The Mystery of Lyle and Louise"

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.

Lustrous, black 'hard coal'.

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.

Chlorite-mica with perfect slaty cleavage.

Brownish gray, translucent.

Red-brown to gray, coarse-grained, containing feldspar and mica.

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