"Avantor"

Give Your Students a Lesson in Economics as Well as Geology

Good grade, brass-yellow copper ore, massive.

Brown, fluorescent crystals intergrown in dolomite rock.

Amphibole group; dark greenish black cleavages, somewhat columnar.

Red, earthy, in natural chunk form; common pigment ore.

Bright blue crystalline veins and coatings in a matrix of mixed copper ore.

Pure kaolinite powder, 200 mesh.

Classic “peacock” aluminum ore.

Cut black mica cleavage sheets.

Coarse-grained plagioclase and pyroxene with some olivine.

Dark gray, with hornblende as the dominant mafic mineral.

Pink and gray bands, with biotite; shows good foliation.

Fine to medium-grained with biotite.

Medium-grained with biotite.

Coarse-grained, with microcline, biotite and horblende phenocrysts.

Earthy, porous calcareous tufa.