1. Minerals

2. What are Minerals? Occurs naturally (not man-made) is a solid
is a chemical compound arranged in an orderly pattern (crystals)
is inorganic (not made from dead plants or animals)
Is an element or a compound (unique chemical formula)

3. Mineral Groups Minerals are grouped by the elements they are made of
Beryl (Emerald)
Calcite
Amethyst

4. Contain oxygen & silica The most abundant group of minerals
Mineral Group
Characteristics
Examples
Silicates
Contain oxygen & silica
The most abundant group of minerals
Quartz, mica
MICA
Quartz

5. (contain oxygen but not silicon) Make up only 5% of the Earth’s crust
Mineral Group
Characteristics
Examples
Non-Silicates
(contain oxygen but not silicon)
Make up only 5% of the Earth’s crust
Include some of the most important minerals
iron, copper, gold, silver, diamonds, rubies
Silver
Copper
Diamond
Gold
Ruby
Iron

6. Carbon & oxygen and a positive ion, such as calcium Calcite (CaCO3)
Mineral Group
Characteristics
Examples
Carbonates
Carbon & oxygen and a positive ion, such as calcium
Calcite (CaCO3)
Calcite with Duftite inclusions

7. Mineral Group
Characteristics
Examples
Oxides
Metallic ion and oxygen
Hematite (Fe2)O3

8. Mineral Group
Characteristics
Examples
Sulfides
Sulfur and a metallic ion
Galena (PbS)
Pyrite (FeS2)

9. Metallic ion, Sulfur & oxygen Barite (BaSO4)
Mineral Group
Characteristics
Examples
Sulfates
Metallic ion, Sulfur & oxygen
Barite (BaSO4)
Barite BaSo4
Barite on Calcite BaSo4 / CaCO3

10. How Do Minerals Form?
1) Cooling of magma (hot, liquid rock and minerals inside the earth (from the mantle))
Fast Cooling = No Crystals (mineraloids)
Medium Cooling = SMALL crystals
Slow Cooling = LARGE crystals

11. How Do Minerals Form?
2) Elements dissolved in liquids (usually water) will reform into crystals as the water evaporates and the dissolved elements recrystalize.

12. Physical Properties of Minerals (can be used to identify the mineral)
Color
Can be misleading
Can vary with the type of impurities

13. Physical Properties of Minerals (can be used to identify the mineral)
Streak
The color of the powdered form of the mineral
The color of the streak can be different than the mineral
Minerals must be softer than the streak plate

14. Streak…can help identify quartz
BUT...

15. Physical Properties of Minerals (can be used to identify the mineral)
Luster
Surface reflection
metallic = shiny like metal
non-metallic = dull, non-shiny surface
Pyrite has a metallic luster
Calcite has a non-metallic luster

16. Metallic Luster

17. Nonmetallic Luster

18. Physical Properties of Minerals (can be used to identify the mineral)
Hardness
How easily a mineral scratches materials
Mohs Hardness Scale
Scale from 1 (softest) to 10 (hardest)
Test by seeing if the mineral can scratch different objects (like human fingernail, copper, penny, glass, steel file)

19. Breaking Properties: Cleavage or Fracture
Cleavage – mineral breaks along a flat surface or into sheets
Fracture – when a mineral breaks with lots of jagged edges

20. Cleavage or Fracture? 1. 2. 4.

21. Extra Special Properties
1. Fluorescence
Fluorescent color under ultraviolet (UV) light
2. Magnetic
Attract magnets
3. Acid reaction
Carbon dioxide gas bubbles off when you drop acid on them
Carbonates!

22. Fluorescence

23. Magnetic

24. Carbonate Acid Reaction