Minerals

I. Minerals – atoms always have the same pattern

A. Minerals have 5 requirements

1. inorganic

2. formed in nature

3. solid

4. atoms hold the same crystalline pattern

5. chemical composition is always the same

II. Structure of mineral

A. Usually in crystal form in one of six possible atomic crystal patterns

1. These patterns are not always perfect, but the pattern is recognizable

a. cubic

b. hexagonal

c. tetragonal

d. orthorhombic

e. triclinic

f. monoclinic

III. Physical Properties of Minerals

A. These properties help identify different minerals and can be addressed in a series of questions

1. Is it shiny? (luster)

2. How hard is it? (usually measured in the Moh’s scale)

3. What is the streak of the mineral and the color of the powder produced?

4. What is the form or shape of the mineral?

5. Does the mineral have a broken surface?

· Cleavage – break along a smooth flat plane

· Fracture – breakage along an irregular surface

6. Is the mineral heavy? (specific gravity)

7. What color is it?

8. Does it have a unique characteristic? (such as smell)