"Avantor"

Feldspar group; greenish gray alkali feldspar, coarse crystalline, some iridescence.

Spinel group; iron-black, massive; natural magnet.

Pyroxene group; dark green, pure cleaved fragments.

Deep purple crystal clusters.

Deep blue, massive, with nepheline; key feldspathoid.

Dark brown to black; polycrystalline zinc ore.

Exemplary display of hexoctahedral crystal shape.

Light gray, fine small clasts.

Brownish black, intermediate stage between peat and bituminous coal.

Classic, very coarse-grained igneous texture.

Gray, fine-grained, massive contact rock.

Fine crystalline, pure calcite.

Compact Plant Fiber Masses.

Dark gray, composed mostly of pyroxene and olivine.

Light gray, fine-grained, well-foliated, schistose.

Gray to brown mudstone with abundant silt.