Mineral Formation 11/20/153-3 pgs. 68-71

•IN: Why are minerals important?

Put your Lab on the books

How do Minerals form?• Almost all minerals can be found in the Earth’s

crust• Some minerals formed when a giant star exploded• Some minerals form here on the Earth• They form in many different environments under

different physical and chemical conditions– Temperature, pressure, chemicals, water

Why are Minerals Important?

• Rocks are made of minerals.

Example,

• Granite– A rock composed of feldspar, mica, and quartz.

FeldsparMica Quartz

Mineral Classification

• Minerals are classified by their chemical composition.–What they are made of–Where they formed

Two Types of Minerals

• Silicates–Contain oxygen and silicon–Make up 90% of the Earth’s crust

• Nonsilcates–Do not contain oxygen and silicon–Make up less than 10% of the Earth’s crust

Properties of MineralsProperties of Minerals• Color• Luster• Streak• Cleavage and Fracture•Hardness•Density• Special Properties

What is mined?Ore – a mineral deposit large

enough and pure enough to be mined for profit.

MiningMining•Mineral ores are nonrenewable

resources.

MiningSurface mining – the removal of

minerals or other materials at or near the Earth’s surface.

MiningDeep mining – the removal of

minerals or other materials from deep within the Earth.

Responsible Mining• Reclamation – the process of

returning land to its original state after mining is completed.

Mica• Shiny and soft• Separate easily into sheets

Unique Minerals

Unique Minerals

Halite• Tastes salty

Unique Minerals

Magnetite• Magnetic

•OUT: What are some ways we could reduce our need for mining?