Part 7

and is: Consult Mineral Chart white 1 gray 2 yellow 3 brown 4 black 5

If the mineral has a nonmetallic luster,

and is: Consult Mineral Chart white 6 gray 7 yellow 8 brown 9 black 10 green 11 blue 12 red or pink 13 purple or 14 violet colorless 15

Mineral Identification Charts

Chart Mineral Streak Remarks Hardness No.

1. METALLIC luster, WHITE color

A. Does not readily leave mark on paper but can be scratched by ordinary pocket knife Native silver Shiny silver Silver-white 2½-3 white, unless color that tarnished tarnishes to gray, black, or yellowish brown; heavy; can be flattened when hit with hammer

2. METALLIC or SUBMETALLIC luster, GRAY color

A. Will leave mark on paper Argentite Shiny, blackish Lead-gray color 2-2½ to lead gray that tarnishes to dull black; knife cuts it smoothly; heavy; may occur as masses and coatings Galena Grayish black Shiny lead-gray 2½ color; heavy; cube-shaped fragments and crystals Graphite Black Steel-gray color; 1-2 greasy feel; very soft; splits into thin flakes B. Does not readily leave mark on paper but can be scratched by ordinary pocket knife Chalcocite Grayish black Shiny lead-gray 2½-3 color that tarnishes to dull black; knife cuts it smoothly; may have black sooty coating; commonly occurs as compact or granular masses Hollandite Black Silvery-gray 4-6 color; may occur as rounded masses C. Cannot be scratched by ordinary pocket knife Braunite Steel gray or Dark steel-gray 6-6½ black color and submetallic luster Hematite Dark reddish brown Steel-gray color; 5½-6½ commonly occurs (may be as granular or softer) compact masses; shiny, scaly variety is specular hematite; notice streak Hollandite Black Silvery-gray 4-6 color; may occur as rounded masses

3. METALLIC luster, YELLOW color

A. Does not readily leave mark on paper but can be scratched by ordinary pocket knife Chalcopyrite Greenish black Brass-yellow or 3½-4 golden-yellow color that may tarnish and show rainbow-like colors; commonly massive; notice streak Gold Shiny golden Shiny yellow 2½-3 yellow color; extremely heavy; flattens when hit with hammer; notice streak B. Cannot be scratched by ordinary pocket knife Pyrite Black, greenish Shiny, pale 6-6½ black, or golden-yellow or brownish black brass-yellow color that may tarnish; occurs as grains, as masses, or as cubes or other crystal shapes; notice hardness and streak

4. METALLIC or SUBMETALLIC luster, BROWN color

A. Does not readily leave mark on paper but can be scratched by ordinary pocket knife Limonite Rusty yellowish Dark-brown color; 5-5½ brown some specimens have a shiny black surface; notice streak B. Cannot be scratched by an ordinary pocket knife Cassiterite Pale brown, pale Brown; 6-7 yellow or white submetallic; heavy; notice streak Hematite Dark reddish brown Dark brown color; 5½-6½ commonly occurs (may be as granular or softer) compact masses; notice streak Limonite Rusty, yellowish Dark brown color; 5-5½ brown some specimens have a shiny black surface; notice streak

5. METALLIC or SUBMETALLIC luster, BLACK color

A. Will leave mark on paper Argentite Shiny, blackish Lead-gray color 2-2½ to lead grey that tarnishes to dull black; knife cuts it smoothly; heavy; may occur as masses and coatings Graphite Black Greasy feel; very 1-2 soft; splits into thin flakes Pyrolusite Black Very soft; will 1-2 soil fingers; may be powdery B. Does not readily leave mark on paper but can be scratched by an ordinary pocket knife Chalcocite Grayish black Shiny lead-gray 2½-3 color that tarnishes to dull black; knife cuts it smoothly; may have a black sooty coating; commonly occurs as compact or granular masses Hollandite Black May occur as 4-6 rounded masses Limonite Rusty, yellowish Some specimens 5-5½ brown have shiny black surface; notice streak C. Cannot be scratched by an ordinary pocket knife Braunite Steel gray or Luster is 6-6½ black submetallic Cassiterite Pale brown, pale Submetallic 6-7 yellow, or white luster; heavy; notice streak Hematite Dark reddish brown Notice streak; 5½-6½ commonly occurs (may be as granular or softer) compact masses Hollandite Black May occur as 4-6 rounded masses Limonite Rusty yellowish Some specimens 5-5½ brown have shiny black surface; notice streak Magnetite Black Fragments cling 6 to a magnet Pitchblende Brownish black Brownish black, 5½ greenish black, or black; radioactive; heavy; may appear dull or greasy

6. NONMETALLIC luster, WHITE color

A. Can be scratched by a fingernail Cerargyrite Shiny white or Appears waxy; 1-1½ gray knife cuts it smoothly; turns violet brown to black when exposed to light Gypsum White Soft; occurs as 2 crystals or as fibrous, granular, compact, or earthy masses Talc White Knife cuts it 1 smoothly; feels soapy or greasy; splits into thin flakes B. 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 C. 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 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 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 cubes 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 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°; common in granite and pegmatite rocks 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 milky quartz, chert, and chalcedony; crystals commonly 6-sided prisms with pyramid-like ends

7. NONMETALLIC luster, GRAY 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 Appears waxy; 1-1½ gray knife cuts it smoothly; turns violet brown to black when exposed to light Gypsum White Soft; occurs as 2 crystals or as fibrous, granular, compact, or earthy masses Sulfur White or pale Will burn with a 1½-2½ yellow blue flame; commonly found as crystals, crusts, or grains Talc White Knife cuts it 1 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 Anhydrite White Commonly occurs 3-3½ as sugary-looking masses Calcite White Dilute 3 hydrochloric acid fizzes on calcite; perfect cleavage in 3 directions gives rhomb-shaped fragments Celestite White Crystals commonly 3-3½ 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 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 Anhydrite White Commonly occurs 3-3½ as sugary-looking masses Celestite White Crystals commonly 3-3½ prism-shaped or flat-looking; some cleavage fragments are 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 Opal White Curved, 5-6 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°; common in granite and pegmatite rocks Opal White Curved, 5-6 conchoidal fracture; may appear glassy, greasy, resinous, or dull Quartz White Curved conchoidal 7 fracture; occurs as chert and chalcedony

8. NONMETALLIC luster, YELLOW color

A. Can be scratched by a fingernail Carnotite Yellow Bright canary 2 yellow or lemon yellow; radioactive; occurs as crusts and powdery masses Gypsum White Yellowish; soft; 2 occurs as crystals or as fibrous, granular, compact or earthy masses Limonite Rusty yellowish Brownish-yellow 1+ brown color; may be soft and earthy 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 Uranophane Light yellow to Yellow to 2-3 light yellow yellow-orange orange color; radioactive B. Cannot be scratched by a fingernail but can be scratched by a copper penny Barite White Rather heavy; 3-3½ cleavage fragments may be flat and slab-like Calcite White Yellowish; dilute 3 hydrochloric acid fizzes on calcite; perfect cleavage in 3 directions gives rhomb-shaped fragments 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 Uranophane Light yellow to Yellow to 2-3 light yellow yellow-orange orange color; radioactive 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 Opal White Curved, 5-6 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 Curved, 5-6 conchoidal fracture; may appear glassy, greasy, resinous, or dull Quartz White Curved conchoidal 7 fracture; brownish-yellow smoky quartz crystals commonly 6-sided prisms with pyramid-like ends; chalcedony and jasper may be a shade of yellow, too

9. NONMETALLIC luster, BROWN color

A. Can be scratched by a fingernail Gypsum White Brownish; soft; 2 occurs as crystals or as fibrous, granular, compact or earthy masses Limonite Rusty yellowish May be soft and 1+ brown earthy 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 B. Cannot be scratched by a fingernail but can be scratched by a copper penny Barite White Rather heavy; 3-3½ cleavage fragments may be flat and slab-like Biotite (black mica) White Dark brown; 2½-3 splits into thin, flat 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 Salty taste; 2½ 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 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 of 90° or near 90°; common in granite and pegmatite rocks Garnet White Commonly occurs 6½-7 as crystals Quartz White Curved conchoidal 7 fracture; brown smoky quartz crystals commonly 6-sided prisms with pyramid-like ends; chalcedony, chert, and jasper may be a shade brown, too Tourmaline White Dark brown 7-7½ variety is dravite; notice hardness, striations on crystals, and triangular cross section of some crystals E. Cannot be scratched by quartz Tourmaline White Dark brown 7-7½ variety is dravite; notice hardness, striations on crystals, and triangular cross section of some crystals

10. NONMETALLIC luster, BLACK color

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