1. Minerals & Rocks

2. Minerals
Naturally occurring, homogeneous substances that are inorganic.
Minerals make up rocks
Feldspar
Quartz

3. Mineral Characteristics
Color
Luster
Hardness
Streak
Cleavage
Crystal structure
Density

4. Color Not a great identifying characteristic
Many minerals are the same color
Some minerals come in many colors

5. Luster The way light is reflected off the surface Metallic Luster
Hard, shiny look, like metal
Nonmetallic Luster
Can still be shiny, but some light passes through

6. Hardness
Ability to scratch other minerals
Mohs’ Scale of Hardness

7. Streak The powdered form of the mineral
Found by rubbing the mineral on an unglazed streak plate

8. Cleavage
Tendency of a mineral to break along flat planes

9. Crystal Structure
Many minerals have distinctive crystal shapes

10. Density Specific Gravity
Ratio of the density of a substance to the density of water
If density = 4 g/ml
Specific gravity = 4