GEOG 104 Physical Geography Lab

MT1: Minerals with Metallic Luster or Dull (Tarnished) Metallic Luster

Reference
Tables

MT1 

MT2 

MT3 

MT4 

MT5 

MT6 

Hardness Streak Cleavage Other Mineral

< 5.5

(does not

scratch glass)

Black, green-black, brown-black, or gray

One

(possibly visible)

Gray to black in color; dull luster; greasy feel

Graphite

C

Three

Silvery gray in color; cubic crystals are common

Galena

PbS

None

Brown to brownish black in color; submetallic luster common, weakly magnetic

Chromite

FeCr2O4

None

Golden yellow to greenish yellow in color; massive

Chalcopyrite

CuFeS2

Yellow-Brown

None

Dark brown to black in color; massive or rounded forms with fiberous layers

Geothite

FeO(OH)

Copper-red

None

Copper to brown in color but may have a green coating; malleable

Native Copper

Cu

>5.5

(scratches glass)

Black or Green-black

None

Brass-yellow in color; massive or as crystals

Pyrite

FeS2

Black

None

Dark gray to black in color; dull luster

Magnetite

Fe3O4

Red-brown

None

Steel gray to dull red in color; massive or may have tiny flakes

Hematite

Fe2O3