Muscovite (white White Light colored; 2-2½ mica) splits into thin, flat, transparent sheets that will bend without breaking Sulfur White or pale Will burn with a 1½-2½ yellow blue flame; commonly found as crystals, crusts, or grains C. Cannot be scratched by a copper penny but can be scratched by an ordinary pocket knife Barite White Rather heavy; 3-3½ cleavage fragments may be flat and slab-like Dolomite White Commonly occurs 3½-4 as granular masses and as rhomb-shaped crystals; dilute hydrochloric acid may fizz slightly on dolomite Fluorite White Cleavage in 4 4 directions can give fragments that are shaped like octahedrons; crystals commonly cube-shaped D. Cannot be scratched by an ordinary pocket knife but can be scratched by quartz Cassiterite Pale brown, pale Brown, reddish 6-7 yellow, or white brown, or yellowish brown; heavy; dull to brilliant luster Feldspar White Glassy or pearly 6 luster; good cleavage in 2 directions that meet at an angle