Mineral Characteristics - Colors and Shapes

Mineral

Characteristic colors

Shape

Observations

1. Minerals floating on surface sometimes forming film.

Graphite

Grey, shiny

Flakes

remain on surface

Micas

White, yellow, black, brilliant

Molybdenite

Light grey, brilliant

Flakes

particularly after crushing

Speculante

Brilliant, black

Fine flakes

Sulphides (pyrite, chalcopyrite, pyrrhotite, etc)

Grey, yellow, metallic

Dust

Gold

Metallic, golden yellow

Fine flakes

2. Minerals forming white ring

Quartz

White, grey mat or shiny

Grain, often fragments with crystaline faces

Largest are included in the next category

Feldspar

White, pale yellow, pink

Calcite

White, pale yellow, grey

Beryl

White, pale yellow, emerald green

3. Outside part of black tongue (black sand)

Fluorite

Violet, green

Grains

Largest identical with next category

Andalusite

White, greyish

Fine elongated prisms

Apatite

Grey, light pinky-brown

Fragments of hexagonal prisms

Tourmaline

Black, dark green

Fragments of prisms with triangular section started longitudinally

Amphiboles

Dirty green, black green

Grains, cleavage 124^o

Pytosenes

Dirty green, black green

Grains, cleavage 90^{o approx}

Pisolites

Rust brown

Grains, more or less spherical

4. Inside part of black tongue (black sand)

Ceylonite

Green

Grains of ten octahedron

Maybe attracted to magnet.
Particular refraction in water.

Topaz

Colorless, light green

Elongated, striated prisms

Kyanite

Pearly white, shimmering blue

Fragments, flattened prisms

Corundum

Light yellow, light grey

Grains

Sphene

Pinky grey

Epidote

Yellowy green

Grains, prism fragments

Staurolite

Dirty brown

Fragment, orthorhombic prisms

Olivine

Olive green

Grains, rounded

Garnets

White, mauve, red-brown

Grains, spherical with many faces

Specularite

Brilliant black

Grains, flake shaped

Ilminite

Purpley-black

Magnetite

Brownish black

Grains, octahedrons

Diamond

White, grey

Octahedrons, sometimes with curved edges, cubes

Zitcon

Grey, colorless, yellow, red

Grains, tetragonal prisms

Rutde

Metallic grey brown

Fragments, prisms with cleavages

Scheelite

Yellowish grey

Grains

Monazite

Dull orange brown

Fragments, fine prisms

5. Bottom of pan

Wolfram

Black

Grains, fragments, prisms

Constant intensity of color and shine when lit from an angle *

Chromite

Black

Grains, octahedrons

Cassiterite

Yellow, dark brown, black

Grains, sometimes cleavages

Columbo-Lantalite

Dull, dark brown

Phortanite

Black

Grains, cubes

Native copper

Pink-red with metallic shine

Grains, specks, flakes

Gold

Gold-yellow, with metallic shine

Grains, spots

Platinum

Grey with metallic shine