Rocks and Minerals

The Rock Cycle

Minerals

• A mineral is a naturally occurring solid that has definite composition and structure

• Scientists use physical properties to identify minerals

Physical Properties of Minerals

• Color• Luster• Hardness• Streak• Cleavage• Magnetism• Odor• Taste

Minerals

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Properties of Minerals

• Color - not always reliable. The color can vary among different samples

• Luster - the way a mineral reflects light– Metallic– Nonmetallic

More Properties of Minerals

• Cleavage - the way in which a mineral breaks

• Hardness - the ability of a mineral to resist being scratched– Mohs’ Hardness Scale• 1-10• Diamond is the hardest mineral (10)

More Properties of Minerals

• Streak - the color of powder when it is rubbed against a ceramic tile

• Magnetism - Magnetite is magnetic

• Odor Sulfur is mineral that smells like rotten eggs

• Taste- Halite is a mineral that tastes like salt

The Importance of Minerals

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3 Types of Rocks

• Metamorphic - formed when tremendous heat and pressure change existing rock

• Igneous - formed when hot liquid magma exits through a volcano

• Sedimentary - formed when sediments are compacted and cemented together

Sedimentary Rocks

Igneous Rocks

Metamorphic Rocks

The Rock Cycle

The Rock Cycle

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