Do Now: Is it made from living material (organic) or not (inorganic)? Plastic Milk Rock River Tree Air Salt Gold Skin Inorganic – non living Organic – living Inorganic – non living Organic – living Inorganic – non living

Organic vs. Inorganic  Organic matter  Carbon (C) and Hydrogen (H)  Example – glucose (C6H12O6)  Inorganic matter  Carbon (C) but no Hydrogen (H) OR  Neither  Examples – Water (H2O) or Carbon Dioxide (CO2)

Minerals of the Earth How can we identify minerals?

1. What is a mineral? a. Made of elements b. 90% of minerals made of only 8 common elements of the Earth’s crust c. Most minerals contain Si and O, called silicates (quartz) d. Most are compounds, made of more than one element (halite is Na + Cl)

ESRT pg. 1

2. What is a mineral? 5 requirements: a. Occurs naturally. b. It is solid. c. Crystalline structure - atoms are arranged in an orderly pattern d. Inorganic (not from living material). e. Unique chemical composition - made of a single element or compound …ie - it is NOT a mixture.

3. What does crystalline structure mean? Atoms are arranged in regular geometrical patterns. Examples:

4. Physical properties are determined by crystalline structure  Structure determines physical properties  Example: Hardness of D iamond (hard) vs. Graphite (soft). Both are made of C atoms arranged in different pattern.

5. How minerals break depends on the arrangement of its atoms Cleavage vs. Fracture  Quartz fractures (strong bonds)  Mica cleaves (weak bonds)

6. Types of minerals Silicates are most common types of mineral -96% of all minerals  compound of 4 Silica around 1 Oxygen  Forms silica tetrahedron  Quartz, feldspar, mica, horneblend are minerals that are considered silicates.

ESRT pg 16 – How many silicates?

6. Types of minerals Carbonates contain carbon  1 Carbon + 3 oxygen  Calcite, dolomite are carbonates

7. How are minerals made?  Hardened magma (under the crust)  Hardened lava (above the crust)  Precipitation in water  Evaporation of water  From other minerals subjected to heat and pressure

Using the 5 requirements, decide whether the following can be minerals. Diamond Water Salt Grass Air

ESRT pg. 16 Mineral Guess Who?

Minerals of the Earth How can we identify minerals?

Tests to identify minerals #1 Color easily identified  Not reliable…Why? Minerals come in different colors Different minerals come in similar colors

Identification of Minerals #2 Luster - how a mineral reflects light  Metallic orNon-metallic

Identification of Minerals #3. Streak is the color a mineral makes when in powder form  Test is to scratch on porcelain tile

Identification of Minerals #4. Hardness  Minerals resistance to scratching  Moh’s Scale of Hardness

Hardness can be compared to common items  1Talcfingernail scratches  3Calcitepenny scratches  5Apatitesteel nail scratches  7Quartzglass scratches  10 DiamondNothing scratches

How hard is it?  Your fingernail scratches the mineral  The mineral scratches the glass plate  The mineral does not scratch the glass plate but does scratch the penny

Identification of Minerals #5 Cleavage  Mineral splits along one or more smooth flat surfaces #6 Fracture  Do not show cleavage  Rough surface, uneven

Identification of Minerals  #7 Density  #8 Magnetic  Magnetite will attract a magnet  #9 Acid test  Calcite will fizz when acid is applied

ESRT pg.16 EXAMPLES Which mineral has a different color in its powdered form than its original form? a) pyriteb) graphite c) kaolinited) magnetite a) PYRITE

ESRT pg. 16 Which mineral contains iron, has metallic luster, is hard, and has the same color and streak? a) biotite micab) galena c) kaolinited) magnetite d) MAGNETITE

What minerals does your rock sample contain?  Describe your rock sample  Color?  Grain size?  Single or multiple minerals?  Cleavage or fracture?