Minerals

What you need to learn

• How minerals form, and which are most common in the Earth’s crust

• Which properties can be used to identify and classify minerals

• Why are certain minerals ores and gems

What is a Mineral?

• A naturally occurring, inorganic solid with a specific chemical composition and a definite crystalline structure

– Earth’s crust contains about 3000

– Has many uses for humans and important for Earth

– Made up of non-living things

– Not man-made

– Atoms are arranged in repeating patterns

Where do they come from?

• Cooling of magma

– Large crystals form when magma cools slowly

– Small crystals form when magma cools rapidly

• Super-saturated solutions

– Large amount of solute in a solution

Mineral groups

–Formed in rock groups

• Silicates (contain silicon, oxygen, and usually more elements

• Carbonates (metallic element with CO3)

• Oxides (oxygen and a metal)

Identifying Minerals

• Color: easy to see, but unreliable

• Luster: how it reflects light, either metallic or non-metallic

• Texture: how it feels

• Streak: color when it is broken up or powdered

• Hardness: how easy it can be scratched

• Cleavage and Fracture: how it breaks

• Density and Specific Gravity: factors of weight and volume

• Special Properties: how light shines through, magnetism, smell

Mineral Uses

• Computers

• Cars

• Televisions

• Desks

• Roads

• Buildings

• Jewelry

• Beds

• Paints Sports equipment

• Medicines

• Mining for profit

– Ores

– Gems