1. What is a Mineral?
6th Grade Science

2. What is a mineral? Definition:
A mineral is a naturally formed, inorganic solid that has a definite crystalline structure.

3. Properties of Minerals:
Solid
Cannot be a liquid or a gas
Naturally Occurring
Found in nature, not man-made
Inorganic
Is not alive and never was, non-living
Fixed composition
Comes from 1 or more elements made by Earth.
Crystal Form
A definite structure in which atoms are arranged

4. Questions to ask yourself when determining if an item is a mineral or not:
Is it non-living material?
Is it a solid?
Is it formed in nature?
Does it have a crystalline structure?
The next few slides show an assortment of items.
As a group, categorize the items as either:
Minerals or Non-Minerals.

5. Wood

6. Gold

7. Fossil

8. Topaz

9. Bones

10. Granite

11. Quartz

12. Pearls

13. Talc

14. Diamond

15. Coal

16. And the answers are… Minerals Non-Minerals Gold Topaz Quartz Talc
Diamonds
Non-Minerals
Wood - once living
Fossils – once living
Bone - living material
Granite - intrusive igneous rock
Pearls – made by oysters
Coal - Sedimentary rock

17. How are minerals identified?
There are over 4,000 minerals
Minerals are identified by their properties --→
Color
streak
hardness
Luster
density
crystal structure
cleavage and fracture
special properties.

18. Color
Both minerals shown here are gold in color. But only one is the mineral gold. Very few minerals have their own characteristic color.

19. Streak
The streak of a mineral is color of its powder. Although the color of a mineral may vary, its streak will not. However the streak and color of a mineral are often different.

20. Hardness
We use Moh’s hardness scale to determine the hardness of a mineral by scratching one mineral against another to determine which is harder. The scale goes from 1-10…..softest to hardest.

21. Luster
Luster is the term to determine how light reflects from a minerals surface. (shiny)

22. Density
Density is the mass per unit volume. No matter how much of a particular mineral sample you have the density always remains the same.

23. Crystal Structure
The atoms that make up a mineral line up in a regular pattern. This pattern repeats over and over. The repeating pattern forms a minerals crystal structure. All crystals of a mineral have the same crystal structure.

24. Cleavage and fracture
Cleavage is when a mineral that splits easily along flat surfaces.
Fracture is when a mineral breaks apart in an irregular way.

25. Special Properties
Some minerals have special properties such as magnetism, conducting electricity, and glowing under UV light.