"gel box"

Study the Formation of Different Igneous Rocks

Classic, dark; from the Columbia Plateau.

Medium-grained with biotite.

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

Glassy; most specimens float in water.

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

Light gray, with flow structure.

Grayish black trap rock.

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

Dark gray with abundant gas pocket vesicles.