1. Chapter 4 Minerals!
Page 84 in your book

2. Fascinating Fact
The elements oxygen, silicon, aluminum, iron, magnesium, calcium, potassium, and sodium make up 99 percent of all minerals on Earth

3. 4.1 What in the heck is a mineral?
= A naturally occurring, inorganic solid that has a specific chemical composition and a definite crystalline structure.
* Minerals are the
building blocks of
rocks!

4. Mineral Characteristics
1. naturally occuring and inorganic
2. definite crystalline structure
3. solids with specific compositions

5. “1. Naturally occurring and inorganic”
Formed only by NATURAL PROCESSES
INORGANIC = not alive and never was alive!
Ex – sugar is NOT a mineral because it came from a plant that was ALIVE!

6. “2. Definite Crystalline Structures”
Crystal is a solid in which the atoms are arranged in repeating patterns.

7. “3. Solids with specific compositions”
must be an actual solid!
And , must have the unique arrangement and correct proportions to be considered a mineral.
Ex – NaCl

8. Get 4 Pieces of paper!
We are going to make a mineral flipbook for identification purposes! (like on page 85)
Step #1- slide your four papers up.
Step #2 – Fold the bottom half UP toward the top
Step #3 – Staple them on the crease!
Step #4 – now label them like page 85
And then we will fill in the characteristics as we go!

9. Mineral I.D. Characteristics!
1. Color
2. Luster
3. Texture
4. Streak
5. Hardness
6. Cleavage and Fracture
7. Density and Specific Gravity

10. 1. Color One of the most noticeable characteristics
Color can be due to trace elements or compounds.
One of the least reliable clues of a mineral’s ID

11. Metallic Nonmetallic 2. Luster Shiny Not shiny
Reflects light
Nonmetallic
Not shiny
Dull – due to chemical composition

12. 3. Texture = How a mineral feels to the touch
Con = Subjective to the tester
Ex – smooth, rough, ragged, greasy, or soapy

13. 4. Streak
When a mineral is rubbed across an unglazed porcelain plate it leaves a colored powdered streak. Only if the mineral is softer than the p. plate!
Nonmetallics typically
leave a white streak
Useful for Metallics ID

14. 5. Hardness = Measure of how easily minerals can be scratched.
Measured by 10 easily recognized minerals developed by Friedrich mohs

15. 6. Cleavage and Fracture
Cleavage Minerals that have cleavage will break in a certain direction where the bonds between atoms are not strong.

16. Fracture
Minerals that do not have cleavage will fracture when they are broken.
If the fracture has a smooth curved surface it is called a conchoidal fracture, otherwise most minerals fracture irregularly

17. 7. Density and Specific Gravity
Sometimes the same mineral may have different weights which make different densities!
D = M/V
Density = mass / volume
Specific Gravity is a better and more accurate measure of density by comparing the ratio of the mass of a substance to the mass of an equal volume of water at 4* C.

18. http://www.rockhounds.com/rockshop/mineral_id/#Ste p4
Geol101/Labs/Minerals/Min10.htm
h_science/tutor/content/pdf/masters/esg3_2.pdf
al%20Properties%20Worksheet.doc