Minerals

Mineral - definition Naturally occurring Inorganic Solid Specific atomic composition Definite atomic structure

Mineral Identification 1. Hardness 2. Streak 3. Cleavage/Fracture 4. Luster 5. Specific Gravity 6. Color

Hardness Is measured by how easy it is to

scratch. Geologists order the hardness by…1. Scratched by a fingernail.2. Scratched by a penny. 3. Scratched by a nail. 4. Scratched by a diamond.

These are not all of the tools geologists use, but it will work for our

experiment.

Mineral Identification Hardness – the ability to resist scratching; ranges

from 1 (softest) to 10 (hardest)

Mineral Systems

If space is not restricted, a mineral will exhibit a crystal pattern with a definite number of sides and specific angles.

Mineral Identification _________ – the color

of the powdered form of a mineral

Streak

Mineral Identification

Cleavage (flat surfaces) or Fracture (no flat surfaces) – the way a mineral __________breaks

Mineral Identification

Fracture: ___________________ Ex. Quartz or obsidian

Mica is probably the best example as it splits into thin sheets. It is said to

have one perfect cleavage.

Calcite and Galena cleave in three directions.

They are said to have three good cleavages.

Not all minerals show cleavage.Those that don’t break along cleavage

surfaces are said to have fracture.

Terminator Baby

LusterRefers to the way light

reflects from the surface of the mineral.

There are two types of luster, Metallic: looks like polished

metal. Nonmetallic: does not look like

polished metal. Nonmetallic can be shiny or dull.

Pyrite has metallic luster

Quartz has nonmetallic luster

Specific Gravity of a Mineral

One mineral property we will not use…COLOR

A mineral can be many different colors. Below is Mica.

Review

RAP

Discovery Channel : Minerals

Silicates Non Silicates

COMMON MINERALS IN THE EARTH

QUARTZ (Silica)

SiO2

CORUNDUM (Alumina) Al2O3

HEMATITE

Fe2O3

CALCITE

CaCO3

DOLOMITE

CaMg(CO3)2

GYPSUM

CaSO4

FLUORITE

CaF2

PYRITE

FeS2

OLIVINE (Mg,Fe)2SiO4

PYROXENE (Mg,Fe)SiO3

AMPHIBOLE

(Ca2Mg5)Si8O22(OH)2

FELDSPARSAlbite NaAlSi3O8

Orthoclase KAlSi3O8

Anorthite CaAl2Si2O8

KAOLINITE Al2Si2O5(OH)4

Discovery Channel : Salt

Common minerals and their uses