1. Minerals, Rocks, and Mineral Resources
EARTH MATERIALS
Minerals, Rocks, and Mineral Resources

2. MINERALS Naturally occurring Inorganic Crystalline solid
Definite chemical composition

3. ARE THESE MINERALS? WHY OR WHY NOT?
Diamond
Coal
Wood
Quartz
Graphite

4. WHAT IS CRYSTALLINE?
The atoms have a specific arrangement called the crystal structure
Every mineral has its own distinctive crystal structure

5. CRYSTAL STRUCTURE The ordered pattern of atoms in the mineral.
Hexagonal
Cubic
Horizontal (thin, flexible sheets)

6. MINERAL FORMATION Atoms organize to form crystalline solids
Recrystallization of atoms from solids and liquids in rock-forming environments

7. MINERAL IDENTIFICATION
The arrangement and type of atoms gives every mineral a set of physical and chemical properties that can be used to identify the mineral.

8. 1. COLOR Many minerals have a characteristic color
Some colors may be caused by impurities
Many minerals come in more than 1 color (variable color).

9. 2. LUSTER The way a mineral looks in reflected light
Metallic—shines like a metal
Nonmetallic—may be shiny, but does not shine like a metal
Glassy, waxy, pearly, earthy (dull)

10. 3. STREAK The color of the powdered form of the mineral
Test performed using an unglazed, porcelain streak plate
The streak color is not always the same color as the mineral

12. 4. HARDNESS Moh’s Scale of Hardness
To test for hardness, scratch the unknown mineral with an object of known hardness.
Objects include glass plate, penny, fingernail.

13. MOH’S SCALE OF HARDNESS
Ranges from 1 to 10.
1 is the softest, 10 is the hardest.

14. 1. Talc
2. Gypsum Fingernail
3. Calcite Copper Penny
4. Fluorite Iron Nail
5. Apatite Glass Plate
6. Feldspar
7. Quartz Streak Plate
8. Topaz
9. Corundum
10. Diamond

15. FRACTURE A mineral breaks producing an uneven breaking surface.
Does NOT follow the atomic arrangement.
Irregular, Fibrous, Curved (conchoidal)

16. CLEAVAGE The ability of a mineral to break along zones of weakness.
Forms smooth to semi-smooth parallel sides or surfaces.
The break will follow the atomic arrangement. Predictable pattern!

17. DENSITY Every mineral has its own specific density.
May be called specific gravity—density compared to water.

18. OTHER PROPERTIES Chemical reaction with HCl—Hydrochloric Acid
Acid reacts with the mineral calcite
Magnetism---