MINERAL IDENTIFICATION CHECKLIST Minerals with Metallic Lustre: MINERAL Galena COLOUR Silver – gray STREAK Gray – black MAGNETIC? No Magnetite Graphite Steel gray – black Gray - black Black Black Yes No Chalcopyrite Pyrite Brassy yellow Brassy beige – yellow Brassy beige – yellow Steel gray – black; rusty brown Black Black No No Black Yes Reddish brown No Lacks cleavage OTHER Well-formed, 12sided crystals Pyrrhotite Hematite OTHER Cubic cleavage, high specific gravity Soft, greasy; marks paper Cubic crystals Minerals with Non-Metallic Lustre: a) Harder than glass MINERAL Garnet COLOUR Reddish brown HARDNESS 7-7.5 CLEAVAGE None Feldspar Pink, gray or white 6-6.5 Quartz Various well-developed cleavages at right angles None COLOUR Brown to black Colourless to beige Colourless White to colourless Colourless, green, purple White Hardness 2.5-3 2.5-3 2-2.5 6-sided crystals with triangular faces b) Softer than glass MINERAL Biotite Muscovite Halite Calcite Fluorite Talc OTHER Thin, elastic sheets Thin, elastic sheets Salty taste Effervesces in HCl acid CLEAVAGE One perfect, basal One perfect, basal Perfect cubic Rhombic; directions at 75 Cubic One (thin scales) Greasy feel