1. Characteristics and Identifications
Minerals
Characteristics and Identifications

2. 5 characteristics that are a must!
What is a Mineral?
5 characteristics that are a must!
1. A mineral is naturally
occurring.
A process that occurs
in the natural world.
Not things such as plastic,
brick, glass and steel to
name a few.

3. 5 characteristic that are a must!
2. Inorganic
3. Solid
Inorganic means it is not and never was living
Can’t be formed from material that was once part of a living thing.
What is coal?
Always a solid
Has Volume
Has Shape
Particles are packed tightly .

4. 5 characteristic that are a must!
4. Crystal Structure
Does Coal have a crystal structure? Nope!
Particles line up in a pattern that repeats over and over again
The crystal has
a flat side called
a face.
Faces meet at sharp edges and corners

5. 5 characteristic that are a must!
5. Definite Chemical Composition
Always has elements or compounds in a specific ratio.
Example is Quartz, has one atom of Silicon (Si) with two atoms of Oxygen.
One part identical to all parts

6. Identifying Minerals
How many minerals do you think have been Identified?

7. Identifying Minerals You need to know 7 different characteristics
Each mineral has a unique identity similar to a fingerprint.
Each “fingerprint” can be identified using different characteristic properties
When you have learned to recognize many of the properties of the minerals, you will be able to identify the common ones around you.
Think about how you can use these to identify common minerals around your everyday life.

8. Identifying minerals
Color (do not rely upon as your only characteristic)
Physical Property
Color can vary among same mineral
Qualitative observations (no standard to what color is)
Each of these is Gold in color
Gold Pyrite Chalcopyrite

9. Identifying minerals Streak Examples Color of the minerals powder
Color can be different from the crystal
form
Color may vary but streak will not
Examples
Hematite may look black but will streak Red/Brown
Pyrite looks yellow-gold but will always streak Gray

10. Identifying minerals Luster
How light reflects off the surface of the mineral.
Minerals containing metal are often shiny and are called metallic.
Other types of luster are Glassy, Waxy, Greasy, Pearly, Dull or Submetallic Silky and earthy.
For our purposes, we’re just going to distinguish between two main types: metallic (shiny) and non-metallic (not shiny).

11. Identifying minerals
Examples B C A E F D

12. Identifying minerals Density = Mass / Volume
No matter how big the sample, density will remain the same

13. Identifying minerals
Hardness
1812 Friedrich Mohs, an Austrian Mineral Expert invented a test to describe the hardness of minerals
Mohs Hardness Scale
Ranks 10 minerals from softest to hardest.
Uses the scratch test.

15. Identifying minerals 6 types of crystal structures
Cubic, Hexagonal, Tetragonal, Orthorhombic, Monoclinic, Triclinic

16. Identifying minerals
Cleavage and Fracture
Cleavage means a mineral breaks easily on a plane (flat surface) like a skipping stone.
Fracture is like broken glass. There is no pattern to how it breaks (randomly).