1. Minerals

2. What is a mineral? Naturally occurring, inorganic solid, with a specific chemical composition and a definite crystalline structure

3. Mineral Characteristics Earth’s crust is composed of 3,000 minerals. Forming of rocks and shaping Earth’s surface. Example: early humans began making tools from iron.

4. Minerals are formed by natural processes. Can not be developed in labs – Exp: synthetic diamonds They are not alive and never were alive.

5. What’s a mineral and what’s not a mineral? Salt is a mineral Sugar is not, because its harvested from plants. What about coal?

6. What’s a mineral and what’s not a mineral? Salt is a mineral Sugar is not, because its harvested from plants. What about coal? – No, millions of years ago it formed from organic materials.

7. Crystalline structure Crystal is a solid which atoms are arranged in repeating patterns A mineral can form in an open space and grow into a large crystal

8. Composition of solids Each type of mineral has its own unique chemical composition. Some might be specific – Copper, Silver, and Sulfur are single elements others might be complex – Quartz (SiO2). Combination of 1 Silicon atom and 2 Oxygen atoms.

9. Rock Forming Minerals Of the 3,000 minerals occur in Earth’s crust, about only 30 are common. 8 -10 are rock forming minerals

10. Composed of 8 common elements in Earth’s crust – Quartz – Feldspar – Mica – Pyroxene – Amphibole – Olivine – Garnet – Calcite

11. Minerals from magma Magma forms below Earth's surface, and rises toward the surface because its less dense. Magma then cools and crystallizes If magma cools slowly, atoms have time to arrange into large crystals If magma reaches water or air and cools quickly, small crystals form

12. Minerals from solutions Most dissolve in water. – Such as salts dissolving in the ocean to make it salty Minerals that form from the evaporation of liquid is called evaporites

13. Identifying Minerals Geologists use several tests to identify minerals – Crystal form – Luster – Hardness – Cleavage & Fracture – Streak – Color – Texture – Density & Specific gravity – Special properties