1. MINERALS
We are what we are!

2. Minerals
 Typical minerals
 Copper – Used in electrical wiring
 Gold – Used for jewelry
 Talc – Baby powder
 Quartz – The main ingredient in glass
 A rock can be defined as an aggregate of
two or more minerals, but there are some
exceptions.

3. Earth Mineral
 An earth mineral is…
 Naturally occurring
 Inorganic
 Solid
 Possesses an orderly internal structure
 Has a definite chemical composition

4. MINERAL GROUPS
RUBY, Garnet, Sapphire, etc.

5. Mineral Groups
 Silicates
 Silicone and Oxygen
 Non-silicates
 Carbonates
 Calcite & Dolomite
 Oxides
 Magnetite
 Sulfides
 Bornite
 Halides
 Fluoride
 Native Elements
 Diamond

6. Silicates
Quartz Oxygen
Feldspar
Silicon
Biotite Silicon Tetrahedron
- The building block
of all Silicates.
Hornblende

7. Silicate Subgroups
Ferromagnesian Non-ferromagnesian
(dark) (light)
Olivine Light Mica
(Muscovite)
Pyroxene group Orthoclase Feldspar
(Augite)
Amphibole group Plagioclase Feldspar
(Hornblende)
Dark Mica Quartz
(Biotite)

8. Non-silicates
 Carbonates
 Calcite & Dolomite
 Oxides
 Magnetite
 Sulfides
 Bornite
 Halides
 Fluoride
 Native Elements
 Diamond

9. PROPERTIES
Hardness, Cleavage, etc.

10. Crystal Form
 External expression of a mineral’s orderly
internal arrangement of atoms.
 Examples
 Pyrite – Cubic
 Quartz – Hexagonal

11. Luster
 The quality of light reflected from the surface
of a mineral.
 Examples
 Galena - Metallic
 Fluorite – Non-metallic

12. Types of Luster
 Metallic The mineral is opaque and reflects light
as a metal would.
 Submetallic The mineral is opaque and dull. The
mineral is dark
 Nonmetallic minerals are described using
modifiers that refer to commonly known
qualities.
 Waxy The mineral looks like paraffin or wax.
 Vitreous The mineral looks like broken glass.
 Resinous The mineral looks like hardened tree
sap.

13. Color
 Unreliable
 Example
 Quartz

14. Streak
 Color of a mineral in its powdered form.
 Examples
 Mematite
 Oolitic
 Color - black
 Steak - black
 Sepoular
 Color - black
 Steak - black

15. Hardness
 The measure of the resistance of a mineral to
scratching.
 Common testing materials
 Copper – 3.5
 Glass – 5.5
 Fingernail – 2.2

16. Hardness [Scale]
Mineral Moh’s Scale Rating
Talc 1
Gypsum 2
Calcite 3
Fluorite 4
Apatite 5
Orthoclase Feldspar 6
Quartz 7
Topaz 8
Corundum 9
Diamond 10

17. Cleavage
 Tendency of a mineral to break along planes
of bonding
 Fracture describes the quality of the
cleavage surface.
 fibrous ( dull, silky) fracture
 conchoidal (curved, shell-like lines) fracture
 irregular (rough, jagged) fracture

18. Cleavage Types
 Cubic Cleaves in three directions at 90° to
one another
 Rhombohedral Cleaves in three directions
but not at 90° to one another
 Octahedral Cleaves in four directions
 Dodecahedral Cleaves in six directions
 Basal Cleaves in one direction
 Prismatic Cleaves in two directions

19. Specific Gravity
 Specific Gravity of a mineral is a comparison
or ratio of the weight of the mineral to the
weight of an equal amount of water. The
weight of the equal amount of water is
found by finding the difference between the
weight of the mineral in air and the weight of
the mineral in water.
 The most common is 2.5 – 3

20. Others
 Taste
 Only soluble minerals have a taste, but it is very
important that minerals not be placed in the
mouth or on the tongue.
 Feel
 Magnetism
 Magnetism is the characteristic that allows a
mineral to attract or repel other magnetic
materials.
 Reaction to Acid