Mineral IdentificationMineral Identification

Identifying Minerals: Identifying Minerals: Minerals have chemical and physical Minerals have chemical and physical

properties that are unique to each mineralproperties that are unique to each mineral

Physical Physical PropertiesProperties

ColorColor LusterLuster Density/specific Density/specific

gravitygravity TextureTexture

Chemical PropertiesChemical Properties

CleavageCleavage HardnessHardness Special properties Special properties

(reaction (reaction w/hydrochloric acid)w/hydrochloric acid)

Crystalline StructureCrystalline Structure

ALL minerals are crystalline.ALL minerals are crystalline.

A crystal is a regular geometric solid A crystal is a regular geometric solid with crystal faces.with crystal faces.

Out of thousands of different minerals, Out of thousands of different minerals, only six basic crystal forms can form.only six basic crystal forms can form.

Crystal Shape/FormCrystal Shape/Form

The orderly arrangement of the atoms or The orderly arrangement of the atoms or ions in the mineral determine its crystal ions in the mineral determine its crystal shape.shape.

The alignment and strength of the bonds The alignment and strength of the bonds between the atoms determine hardness, between the atoms determine hardness, cleavage, crystal shape, streak, etc.cleavage, crystal shape, streak, etc.

Six Crystal Six Crystal FormsForms

CubicCubic OrthorhombicOrthorhombic TetragonalTetragonal TriclinicTriclinic HexagonalHexagonal MonoclinicMonoclinic

ColorColor

While helpful not always a reliable feature.While helpful not always a reliable feature.

For example: fluorite & quartzFor example: fluorite & quartz

Fluorite

LusterLuster

The way a mineral reflects lightThe way a mineral reflects light

Metallic or non-metallicMetallic or non-metallic

HardnessHardness

Hardness is how easily a mineral can Hardness is how easily a mineral can be scratched.be scratched.

Talc can be scratched with your Talc can be scratched with your fingernail, while diamonds can cut fingernail, while diamonds can cut glass.glass.

Moh’s Hardness ScaleMoh’s Hardness Scale

Categorizes minerals by hardnessCategorizes minerals by hardness

Ranges from 1(softest) to 10 Ranges from 1(softest) to 10 (hardest)(hardest)

Hardest mineral = DiamondHardest mineral = Diamond Softest mineral = TalcSoftest mineral = Talc

Moh’s Hardness ScaleMoh’s Hardness Scale

StreakStreak

Is the color of a mineral when Is the color of a mineral when powdered.powdered.

When a mineral is rubbed across a When a mineral is rubbed across a porcelain tile a streak of a particular porcelain tile a streak of a particular color will be left.color will be left.

Cleavage and Fracture

If a mineral splits along planes of its If a mineral splits along planes of its surfaces, it has surfaces, it has cleavagecleavage..

If a mineral leaves a jagged edge it is If a mineral leaves a jagged edge it is said to have said to have fracturefracture..

Other PropertiesOther Properties

Some minerals have characteristics Some minerals have characteristics unique to them.unique to them.

Magnetite is attracted to magnets.Magnetite is attracted to magnets.

Calcite fizzes with acid and splits Calcite fizzes with acid and splits images into two separate images images into two separate images when looking through a sample .when looking through a sample .