1. Minerals What is a mineral? How do minerals form?
How can minerals be identified?

2. Key Terms To be a Mineral, Something Must. . .
Crystal form
Lattice
Density
Luster
Inorganic
Streak
Chemical formula
Hardness
Cleavage
Fracture
Minerals are the building blocks of rocks, and therefore of the earth itself.
To be a Mineral, Something Must. . .

3. Naturally Occurring Naturally Occurring Solid Inorganic
Orderly Crystal Grid or Lattice
Have A Definite Chemical Formula
Naturally occurring means the substance cannot be human-created.
For example:
Ice found in snowflakes or glaciers are minerals
Ice in your kitchen freezer is not made naturally and is not a mineral.
Liquids and gases can become minerals only if they change to a solid.

4. Solid Solid Always solid state of matter Definite volume and shape
Naturally Occurring
Solid
Inorganic
Orderly Crystal Grid or Lattice
Have A Definite Chemical Formula
Always solid state of matter
Definite volume and shape
Particles are packed together very tightly
Cannot move compared to a liquid or gas

5. Inorganic or Organic Inorganic
Naturally Occurring
Solid
Inorganic
Orderly Crystal Grid or Lattice
Have A Definite Chemical Formula
Inorganic means carbon that comes from living things is not present.
Minerals are not formed from organic materials such as plant or animal remains.

6. Crystalline Grid or Lattice
Naturally Occurring
Solid
Inorganic
Orderly Crystal Grid or Lattice
Have A Definite Chemical Formula
The atoms in minerals are arranged in an orderly pattern that repeats itself throughout the substance
This structure, because of the chemical formula, is called crystalline.

7. Crystalline Grid a/k/a Lattice
Naturally Occurring
Solid
Inorganic
Orderly Crystal Grid or Lattice
Have A Definite Chemical Formula
Notice the difference in a mineral’s orderly and repeating structure when compared to the randomly arranged atom of a non- mineral.

8. Definite Chemical Formula
Naturally Occurring
Solid
Inorganic
Orderly Crystal Grid or Lattice
Have A Definite Chemical Formula
When the atoms are the same in number and type, the chemical formula is known.
Regardless of the state of matter (solid, liquid, or gas) a specific mineral will have the same formula throughout. Common formulas are:
Water: H2O Diamonds: C

9. Minerals Form in Four Ways
Crystallization from magma or other liquids
Precipitation from solution
Heat and Pressure
Hydrothermal solutions
Crystalline structure can occur when melted rock material cools into a solid.
Water will crystalize when a lake freezes over and ice covers its surface.

10. Minerals Form in Four Ways
Crystallization from magma or other liquids
Precipitation from solution
Heat and Pressure
Hydrothermal solutions
Minerals dissolved in water (solution) can precipitate (fall to the bottom) when the concentration is high enough.

11. Minerals Form in Four Ways
Crystallization from magma or other liquids
Precipitation from solution
Heat and Pressure
Hydrothermal solutions
Extreme heat and pressure in the Earth can cause minerals to change form – without actually melting them.
Because of this, different chemical bonds can form that changes the crystal lattice.

12. Minerals Form in Four Ways
Crystallization from magma or other liquids
Precipitation from solution
Heat and Pressure
Hydrothermal solutions
Beneath the Earth’s surface water is super-heated so that it remains liquid instead of becoming steam.
When this super-heated chemical solution contacts rocks and other minerals a new mineral is formed as a result other the chemical reaction.

13. Mineral Identification
Color – Natural appearance
Streak – Powdered form
Luster – Metallic or Non- Metallic

14. Mineral Identification
Hardness – Moh’s Hardness Scale
Crystal System – Six structures

15. Other Methods of Mineral Identification
Density – Mass per unit of volume
(D = Mass/Volume)
Cleavage and Fracture – how does it break?
Special Properties – optical or electrical properties