Part 5

A. Cannot be scratched by a fingernail but can be scratched by a copper penny Biotite (black mica) White Splits into thin, 2½-3 flat sheets that will bend without breaking B. Cannot be scratched by an ordinary pocket knife but can be scratched by quartz Garnet White Commonly occurs 6½-7 as crystals Quartz White Curved conchoidal 7 fracture; brownish-black smoky quartz crystals commonly 6-sided prisms with pyramid-like ends; _chalcedony_ and _chert_ may be black, too Tourmaline White Black variety is 7-7½ _schorl_; notice hardness, striations on crystals, and triangular cross section of some crystals C. Cannot be scratched by quartz Tourmaline White Black variety is 7-7½ _schorl_; notice hardness, striations on crystals, and triangular cross section of some crystals

11. NONMETALLIC luster, GREEN color

A. Can be scratched by a fingernail Amphibole asbestos White Made up of 1-2½ slender, flexible fibers that can be pulled apart Cerargyrite Shiny white or Light greenish 1-1½ gray color; appears waxy; knife cuts it smoothly; turns violet brown to black when exposed to light Muscovite (white White Light colored; 2-2½ mica) splits into thin, flat, transparent sheets that will bend without breaking Sulfur White or pale Greenish; will 1½-2½ yellow burn with a blue flame; commonly found as crystals, crusts, or grains Talc White Light greenish 1 color; knife cuts it smoothly; feels soapy or greasy; splits into thin flakes B. Cannot be scratched by a fingernail but can be scratched by a copper penny Amphibole asbestos White Made up of 1-2½ slender, flexible fibers that can be pulled apart Biotite (black mica) White Dark green; 2½-3 splits into thin, flat, translucent sheets that will bend without breaking Calcite White Dilute 3 hydrochloric acid fizzes on calcite; perfect cleavage in 3 directions gives rhomb-shaped fragments Halite White Greenish tint; 2½ salty taste; dissolves in water; cube-shaped cleavage fragments Muscovite (white White Light colored; 2-2½ mica) splits into thin, flat, transparent sheets that will bend without breaking Serpentine White Two kinds: silky 2½-4 and fibrous, waxy and platy Sulfur White or pale Greenish; will 1½-2½ yellow burn with a 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 Fluorite White Cleavage in 4 4 directions can give fragments shaped like octahedrons; crystals commonly cubes Malachite Green Bright green 3½-4 color; dilute hydrochloric acid will fizz on malachite Serpentine White Two kinds: silky 2½-4 and fibrous, waxy and platy D. Cannot be scratched by an ordinary pocket knife but can be scratched by quartz Feldspar White Glassy or pearly 6 luster; good cleavage in 2 directions that meet at an angle of 90° or near 90° Garnet White Commonly occurs 6½-7 as crystals

12. NONMETALLIC luster, BLUE color

A. Cannot be scratched by a fingernail but can be scratched by a copper penny Anhydrite White Commonly occurs 3-3½ as sugary-looking masses Barite White Rather heavy; 3-3½ cleavage fragments may be flat and slab-like Calcite White Dilute 3 hydrochloric acid fizzes on calcite; perfect cleavage in 3 directions gives rhomb-shaped fragments Celestite White Not quite as 3-3½ heavy as barite; crystals commonly prism-shaped or flat-looking; some cleavage fragments are flat and slab-like Halite White Salty taste; 2½ dissolves in water; cube-shaped cleavage fragments B. Cannot be scratched by a copper penny but can be scratched by an ordinary pocket knife Anhydrite White Commonly occurs 3-3½ as sugary-looking masses Azurite Blue Bright, intense 3½-4 blue color; dilute hydrochloric acid will fizz on azurite Barite White Rather heavy; 3-3½ cleavage fragments may be flat and slab-like Celestite White Not quite as 3-3½ heavy as barite; crystals commonly prism-shaped or flat-looking; some cleavage fragments are flat and slab-like Fluorite White Cleavage in 4 4 directions can give fragments that are shaped like octahedrons; crystals commonly cube-shaped Opal White Curved, 5-6 conchoidal fracture; may appear glassy, greasy, resinous, or dull; milky white and bluish-white precious opal shows plays of colors C. Cannot be scratched by an ordinary pocket knife but can be scratched by quartz Feldspar White Glassy or pearly 6 luster; good cleavage in 2 directions that meet at an angle of 90° or near 90° Opal White Curved, 5-6 conchoidal fracture; may appear glassy, greasy, resinous, or dull; milky white and bluish-white precious opal shows plays of colors Quartz White Curved conchoidal 7 fracture; occurs as crystalline quartz and as bluish _chalcedony_ D. Cannot be scratched by quartz Topaz White Perfect basal 8 cleavage gives flat, plate-like fragments; notice hardness

13. NONMETALLIC luster, RED or PINK color

A. Can be scratched by a fingernail Gypsum White Reddish; soft; 2 occurs as crystals or as fibrous, granular, compact, or earthy masses Hematite Dark reddish brown Brownish-red 1+ color; soft and earthy Sulfur White or pale Reddish; will 1½-2½ yellow burn with blue flame; commonly found as crystals, crusts, or grains B. Cannot be scratched by a fingernail but can be scratched by a copper penny Anhydrite White Pinkish tint; 3-3½ commonly occurs as sugary-looking masses Barite White Pinkish tint; 3-3½ rather heavy; cleavage fragments may be flat and slab-like Calcite White Pink color; 3 dilute hydrochloric acid fizzes on calcite; perfect cleavage in 3 directions gives rhomb-shaped fragments Cinnabar Dark red Dark red or 2½ bright yellowish-red color; shiny, brilliant luster when pure; dull and earthy when impure; heavy Halite White Reddish tint; 2½ salty taste; dissolves in water; cube-shaped cleavage fragments Sulfur White or pale Reddish; will 1½-2½ yellow burn with 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 Anhydrite White Pinkish tint; 3-3½ commonly occurs as sugary-looking masses Barite White Pinkish tint; 3-3½ rather heavy; cleavage fragments may look flat and slab-like Dolomite White Pink color; 3½-4 commonly occurs as granular masses and as rhomb-shaped crystals; dilute hydrochloric acid may fizz slightly on dolomite Fluorite White Pink color; 4 cleavage in 4 directions can give fragments that are shaped like octahedrons; crystals commonly cubes Opal White Reddish color; 5-6 curved, conchoidal fracture; may appear glassy, greasy, resinous, or dull D. Cannot be scratched by an ordinary pocket knife but can be scratched by quartz Feldspar White Glassy or pearly 6 luster; good cleavage in 2 directions that meet at an angle of 90° or near 90° Garnet White Commonly occurs 6½-7 as crystals Opal White Reddish color; 5-6 curved, conchoidal fracture; may appear glassy, greasy, resinous, or dull Quartz White Curved, 7 conchoidal fracture; occurs as _rose quartz_, as pink _chert_, and as _agate_ and _jasper_

14. NONMETALLIC luster, PURPLE or VIOLET color