Mineral Name Possible Colors Streak Hardness Cleavage HEFT Luster Other Light, (how many Properties planes) Medium, Metallic or Heavy Fracture Fluorite Green, yellow, White 4 Cleaves Medium Vitreous purple (glassy) Biotite Brown None 2.5-3 Cleaves 1 plane Light Vitreous, glassy Very flexible Calcite Clear to milky, White 3 Cleavage Light Glassy to earthy Mineral takes a orange, blue rhombic shape Reacts with acid Feldspar Gray, green Colorless 6 Two planes of Light Vitreous orange cleavage that (glassy) meet at right angles Graphite Grey Grey 1.2 Cleavage Light to Dull Alabaster Pinkish-white, White 1.5-2 scratches Cleaves Light Pearly-Earthy Gypsum white, grey, with fingernail reddish-brown
Mineral Name Possible Colors Streak Hardness Cleavage (how many planes) or Fracture HEFT Light, Medium, Heavy Luster Other Properties Fluorite Green, yellow, purple White 4 Cleaves Medium Vitreous (glassy) Biotite Brown None 2.5-3 Cleaves 1 plane Light Vitreous, glassy Very flexible Calcite Clear to milky, orange, blue White 3 Cleavage Light Glassy to earthy Mineral takes a rhombic shape Reacts with acid Feldspar Gray, green orange Colorless 6 Two planes of cleavage that meet at right angles Light Vitreous (glassy) Graphite Grey Grey 1.2 Cleavage Light to Dull Alabaster Gypsum Pinkish-white, white, grey, reddish-brown White 1.5-2 scratches with fingernail Cleaves Light Pearly-Earthy Metallic