Chapter 2 Minerals Reading: 2.1-2.6

Relationships to Earth Systems Biosphere Hydrosphere Atmosphere Lithosphere Calcite Limestone, Halite, Clay minerals

2.1 What is a Mineral? A mineral is a naturally occurring, inorganic solid, with a definite chemical composition and crystalline structure.

Is Ice a Mineral? According to our definition? Naturally occurring? Inorganic? Solid? Chemical composition ? Crystalline structure?

2.2 Chemical Composition First lets go to Atoms ! All matter is made of Atoms. Every speck of Gas, liquid, or Solid surrounding you is a mix of millions of Atoms.

Atoms and Elements

“The Big 8” Most Abundant Elements in Earth Crust

Charging Particles: Ions Positive Charge + Cation (1-8) Negative Charge – Anion (1-4)

Other Bonds Covalent Bond Metallic Bond Between 2 Nonmetals neither one donates or gives up an electron, They simply Share in outer orbital shell forming Covalent bond Metallic Bond very few electrons in the outer most electron shells. Instead of donating or sharing these electrons are released from the orbital shell and available for a nearby cluster of atoms to use. “floting in a sea of Electrons”

Formulating Compounds SiO2 (Mg, Fe)2SiO4

2.3 Crystalline Nature of Minerals A crystal is any substance whose atoms are arrange in a regular, periodically repeated pattern. When atoms combine to form minerals they so in organized way that forms a geometric pattern called crystal.

Crystals

Minerals and Rocks Room 222 ( Geology Building). Geology Building lobby Museum ?

Physical Properties of Minerals 1 Crystal habit (shape) 2) Cleavage & fracture 3) Hardness 4) Specific gravity 5) Color 6) Streak 7) Luster Others (Taste, Reaction to Acid, magnetism. )

Crystal Habit Quartz: elongated crystals Quartz: no characteristic shape

Cleavage & Fracture

Mohs Mineral Hardness Scale

Specific Gravity Quartz 2.7 Au 19

Color

Luster

Other

Mineral Classes

Silicates Si O

Carbonates

2.6 Commercially Important Minerals

Important Minerals

2.7 Harmful and Dangerous Roks and Minerals Asbestos. Feldspar  Quartz

Next Class Rocks