Minerals! What is a mineral? In order for a substance to be classified as a mineral it must maintain...

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Minerals!

What is a mineral?

• In order for a substance to be classified as a mineral it must maintain FIVE characteristics.

• 1. Naturally occurring

• 2. Inorganic• 3. Solid• 4. Definite chemical

composition• 5. Definite crystal

pattern (shape)

Describe each characteristic!Naturally Occurring

Not man made, must occur in nature

Inorganic

Not living and not made of any living materials

Solid

A substance with a definite shape and volume

Definite Chemical Composition

A specific formula (either a single element or a compound)

Definite Crystal Pattern

A specific shape from which the mineral crystallizes or grows atomically

What does the abundance of each mineral depend on?

• Where they form. Location within the earth!

• The rate at which they form. Speed!

• The abundance of the elements from which they form.

There are 2500 known minerals, but only 20 are common , they are referred to as ROCK

FORMING MINERALS

QUARTZ CALCITE AUGITE HEMATITE MICA

FELDSPAR AMPHIBOLE DOLOMITE GYPSUM OLIVINE

All minerals are broken into mineral groups based on their CHEMICAL COMPOSITION!

• 1. Silicates ****• 2. Sulfides• 3. Sulfates• 4. Carbonates• 5. Oxides• 6. Native Elements• 7. Halides • *ate = Oxygen• *ide = Metal

Quartz SiO2

Silicon 2 Oxygen

protons

neutrons electrons

atoms

elements

minerals

silicates sulfides sulfates oxides halides carbonates Native Elements

Silicon+

Oxygen

Sulfur+

Metal

Sulfur+

Oxygen

Oxygen +

Metal

Chlorine and /or

Bromineand/or

Fluorineand/orIodine

+metal

Carbon+

Oxygen

Any Single Eleme

nt

A Mineral is ?

•1. Naturally occurring•2. Inorganic•3. Solid•4. Definite chemical composition•5. Definite crystal pattern (shape)

There are 2500 known minerals, but only 20 are common, they are referred to as ROCK

FORMING MINERALS

Quartz Feldspar

Regardless of the number of minerals in the world each has its own unique set of characteristics.

These characteristics are referred to as:

Physical properties

Physical PropertiesColor

Visual property easiest to identify, but least reliable!

dolomite talc

malachite copper

Luster The way a mineral reflects the light.

Metallic

Non-metallic

Looks or reflects the light like metal

Does not reflect the light as metal

Breakage Result of arrangement of atoms, bonding

Cleavage: to break along a smooth plain or in a particular pattern.

BreakageFracture: To break with uneven, rough, or

jagged edged. No pattern

Streak The powdered residue left behind as a mineral is rubbed across a porcelain tile.

CrystallizationA mineral grows by crystallizing: the arrangement of atoms in a repeating pattern. Minerals crystallize as magma cools-Slow cooling, large crystalsFast cooling, small crystals

Growth

Atomic structure Outward appearance

Crystal (Shapes) Structures

orthorhombicmonoclinic

tetragonal

hexagonal

tricliniccubic

HardnessThe ability of a mineral to resist being scratched.

Relative hardnessAbsolute hardness

Comparison of mineral hardness. -Talc is the softest -Diamond is the hardest.

Physical test using a series of items and recording the numerical measurement.

Example:Apatite is harder than Fluorite, softer than Feldspar.

Example:Feldspar is not scratched by the penny, nail, or file. Its hardness is >6.

estimate

exact

Example

Luster Color Hardness Unique Feature

Streak Chemical Composition

Crystal (Shapes) Structures

Structure: hexagonal

Formula: SiO2