MineralsMineralsReview of Foldable NotesReview of Foldable Notes

What is a Mineral?What is a Mineral?• Formed by natural process.Formed by natural process.• Inorganic – are not made by a Inorganic – are not made by a

life process.life process.• Has a chemical composition.Has a chemical composition.• Crystalline solids – repeating Crystalline solids – repeating

pattern of atomspattern of atoms

• ~ 4,000 minerals on the Earth.~ 4,000 minerals on the Earth.

The Structure of MineralsThe Structure of Minerals• Crystal – is a solid. Crystal – is a solid.

– In this solid form atoms are In this solid form atoms are arranged in a arranged in a repeating patternrepeating pattern..

• 6 Major crystal systems 6 Major crystal systems (Figure 3, p. 10)(Figure 3, p. 10)

6 Crystal Systems6 Crystal Systems

• 1. Cubic – ex: Fluorite. 1. Cubic – ex: Fluorite. • 2. Hexagonal – ex: Quartz.2. Hexagonal – ex: Quartz.• 3. Tetragonal – ex: Zircon.3. Tetragonal – ex: Zircon.• 4. Orthorhombic – ex: Barite.4. Orthorhombic – ex: Barite.• 5. Monoclinic – ex: Orthoclase.5. Monoclinic – ex: Orthoclase.• 6.Triclinic – ex: Rhodonite.6.Triclinic – ex: Rhodonite.

Crystal FormationCrystal Formation

• Crystals form 2 natural Crystals form 2 natural processes:processes:

– MagmaMagma

– From SolutionFrom Solution

Magma CrystalsMagma Crystals

• Magma = melted rock. Cools Magma = melted rock. Cools when reaches Earth’s surface.when reaches Earth’s surface.

• As magma cools – Atoms loose As magma cools – Atoms loose energy and its atoms move energy and its atoms move closer together.closer together.

• Slow Cooling Magma – Large Slow Cooling Magma – Large crystalscrystals

• Fast Cooling Magma – Small Fast Cooling Magma – Small CrystalsCrystals

Crystals in SolutionCrystals in Solution

• Water evaporates and leaves Water evaporates and leaves ions / minerals.ions / minerals.

• Occurs in a dry climate.Occurs in a dry climate.

• Ex: Salt water.Ex: Salt water.

• Crystal formation in solution can Crystal formation in solution can occur if too much of a substance occur if too much of a substance is dissolved in water.is dissolved in water.

• Will form crystals in the solution.Will form crystals in the solution.

• This is called This is called precipitationprecipitation..

Mineral Composition and Mineral Composition and GroupsGroups• 98 % of Earth’s crust is composed 98 % of Earth’s crust is composed

of 90 naturally occurring elements.of 90 naturally occurring elements.

• 8 Common minerals of Earth’s crust8 Common minerals of Earth’s crust– Oxygen, Silicon, Aluminum, Iron, Oxygen, Silicon, Aluminum, Iron,

Calcium, Sodium, Potassium, Calcium, Sodium, Potassium, &Magnesium.&Magnesium.

SilicatesSilicates

• Silicates – minerals that contain Silicates – minerals that contain Silicon (Si), Oxygen (O), and Silicon (Si), Oxygen (O), and usually 1 more element.usually 1 more element.

• Silicon and Oxygen are the most Silicon and Oxygen are the most abundant elements of the abundant elements of the Earth’s crust.Earth’s crust.

CalciteCalcite