Rocks & Rocks & MineralsMinerals

MineralsMinerals

What is a Mineral?What is a Mineral?

Naturally OccurringNaturally Occurring InorganicInorganic SolidSolid Definite Chemical FormulaDefinite Chemical Formula Definite Crystal StructureDefinite Crystal Structure

Naturally OccurringNaturally Occurring

Formed by natural processes not in Formed by natural processes not in the laboratorythe laboratory

- Is an Ice Cube a mineral?- Is an Ice Cube a mineral?

- Is the ice on the windshield of a car - Is the ice on the windshield of a car aa

mineral?mineral?

InorganicInorganic

Formed by inorganic processes; not Formed by inorganic processes; not livingliving

Does not contain chains of carbon Does not contain chains of carbon atomsatoms

SolidSolid

Not gas or liquidNot gas or liquid

-H-H22O as ice in a glacier is a mineral, O as ice in a glacier is a mineral, but but

water is notwater is not

Definite Crystal StructureDefinite Crystal Structure

Highly ordered atomic arrangement Highly ordered atomic arrangement of atoms in regular geometric of atoms in regular geometric patterns patterns

8

Apatite

Feldspar

Diamond

Quartz

Definite Chemical FormulaDefinite Chemical Formula

Minerals are expressed by a specific Minerals are expressed by a specific chemical formulachemical formula

-Gold (Au)-Gold (Au)

-Calcite (CaCO-Calcite (CaCO33))

-Quartz (SiO-Quartz (SiO22))

-Pyrite (FeS-Pyrite (FeS22))

Composition of the Earth’s Composition of the Earth’s CrustCrust

Eight Elements that make up over 98% Eight Elements that make up over 98% of Earth’s Crustof Earth’s Crust-Oxygen (O)-Oxygen (O)-Silicon (SI)-Silicon (SI)-Aluminum (Al)-Aluminum (Al)-Iron (Fe)-Iron (Fe)-Calcium (Ca)-Calcium (Ca)-Sodium (Na)-Sodium (Na)-Potassium (K)-Potassium (K)-Magnesium (Mg)-Magnesium (Mg)

Where Do Minerals Come Where Do Minerals Come From?From?Magma

Evaporation

How Are Minerals Identified?How Are Minerals Identified?

ColorColor LusterLuster HardnessHardness StreakStreak DensityDensity Crystal ShapeCrystal Shape Cleavage and FractureCleavage and Fracture Special PropertiesSpecial Properties

ColorColor Usually the first and most easily Usually the first and most easily

observedobserved

-Some minerals are always the same -Some minerals are always the same colorcolor

-Some minerals can have many -Some minerals can have many colorscolors

QUARTZROSE QUARTZ SMOKY QUARTZ

LusterLuster General appearance of a mineral General appearance of a mineral

surface in reflected lightsurface in reflected light

Glassy-Obsidian

HardnessHardness Resistance to scratching by different items; Resistance to scratching by different items;

“scratchability”“scratchability”

Mohs Hardness ScaleMohs Hardness Scale>2 fingernail >2 fingernail 3 penny 3 penny ~5 Steel of a pocket knife ~5 Steel of a pocket knife 5.5 Window Glass5.5 Window Glass6.6 Steel of a file 6.6 Steel of a file 7 quartz crystal 7 quartz crystal

Mohs Mineral Hardness Mohs Mineral Hardness ScaleScale

1) Talc 1) Talc

2) Gypsum 2) Gypsum

3) Calcite 3) Calcite

4) Flourite 4) Flourite

5) Apatite 5) Apatite

6) Feldspar 6) Feldspar

7) Quartz 7) Quartz

8) Topaz 8) Topaz

9) 9) Corundum Corundum

10) Diamond10) Diamond

Softest

Hardest

1

2

3

4

5

6

7

8

9

10

StreakStreak

The color of a finely powdered mineral The color of a finely powdered mineral Determined by rubbing the mineral on a Determined by rubbing the mineral on a

piece of unglazed porcelain (streak plate)piece of unglazed porcelain (streak plate)

DensityDensity

The amount of matter in a given The amount of matter in a given space (Mass/Volume)space (Mass/Volume)

Crystal ShapeCrystal Shape

Minerals have a characteristic crystal Minerals have a characteristic crystal shape resulting from the atomic shape resulting from the atomic packing of the atoms when the packing of the atoms when the mineral is formingmineral is forming

Cleavage and FractureCleavage and Fracture CleavageCleavage is the tendency of a is the tendency of a

mineral to split or crack along mineral to split or crack along parallel or flat planesparallel or flat planes

FractureFracture occurs when a mineral occurs when a mineral breaks at random lines instead of breaks at random lines instead of at consistent cleavage planes.at consistent cleavage planes.

BIOTITE QUARTZ Obsidian

No Cleavage 1 Direction of Cleavage

Conchoidal Fracture

Special PropertiesSpecial Properties

Magnetism (Magnetite)Magnetism (Magnetite) Glowing under ultraviolet light Glowing under ultraviolet light

(Fluorite)(Fluorite) Salty taste (Halite)Salty taste (Halite) Smell (Sulfur)Smell (Sulfur) Reaction to HCl (Calcite)Reaction to HCl (Calcite)

Magnetite

Economic Importance of Economic Importance of MineralsMinerals

Minerals are in many things we see Minerals are in many things we see and use everyday such as; bricks, and use everyday such as; bricks, glass, cement, plaster, iron, goldglass, cement, plaster, iron, gold

Every American Requires Every American Requires 40,000 Pounds of New Minerals 40,000 Pounds of New Minerals

per Yearper Year at this level of consumption the average newborn at this level of consumption the average newborn

infant will need a lifetime supply of:infant will need a lifetime supply of:-795 lbs of lead (car batteries, electric -795 lbs of lead (car batteries, electric components)components)-757 lbs of zinc (to make brass, rubber, paints)-757 lbs of zinc (to make brass, rubber, paints)-1500lbs of copper (electrical motors, wirings-1500lbs of copper (electrical motors, wirings-3593 lbs aluminum (soda cans, aircraft)-3593 lbs aluminum (soda cans, aircraft)-32,700 lbs of iron (kitchen utensils, automobiles, -32,700 lbs of iron (kitchen utensils, automobiles, buildings) buildings)-28,213 lbs of salt (cooking, detergents)-28,213 lbs of salt (cooking, detergents)-1,238,101 lbs of stone, sand, gravel, cement -1,238,101 lbs of stone, sand, gravel, cement (roads, homes, etc.)(roads, homes, etc.)

RocksRocks

RocksRocks

Made of two or more different Made of two or more different minerals that have been: minerals that have been: cemented togethercemented togethersqueezed and heated together squeezed and heated together melted and cooled together. melted and cooled together.

Types of RocksTypes of Rocks

IgneousIgneous SedimentarySedimentary MetamorphicMetamorphic

Igneous RocksIgneous Rocks

Most igneous rocks are produced Most igneous rocks are produced deep underground by the cooling and deep underground by the cooling and hardening of magmahardening of magma

Sedimentary RocksSedimentary Rocks

Formed from the breaking apart of Formed from the breaking apart of other rocks (igneous, metamorphic, other rocks (igneous, metamorphic, or sedimentary rocks) and the or sedimentary rocks) and the cementation, compaction and cementation, compaction and recrystallization of these broken recrystallization of these broken pieces of rockpieces of rock

Fact about the Mississippi Fact about the Mississippi RiverRiver

Did You Know?Did You Know?

The Mississippi River carries an The Mississippi River carries an average of 436,000 tons of sediment average of 436,000 tons of sediment each dayeach day

It moves an average of 159,000,000 It moves an average of 159,000,000 tons of sediment a yeartons of sediment a year

Metamorphic RocksMetamorphic Rocks

Formed from heat and pressure Formed from heat and pressure changing the original or parent rock changing the original or parent rock into a completely new rock. The into a completely new rock. The parent rock can be either parent rock can be either sedimentary, igneous, or even sedimentary, igneous, or even another metamorphic rock.another metamorphic rock.

The Rock CycleThe Rock Cycle

The diagram of the rock cycle shows how The diagram of the rock cycle shows how the earth's rocks are changed again and the earth's rocks are changed again and againagain

Classification of Igneous Classification of Igneous RocksRocks

CompositionComposition-refers to the minerals -refers to the minerals that make up the rockthat make up the rock

TextureTexture-shape, size, arrangement -shape, size, arrangement and distribution of minerals that and distribution of minerals that make up the rockmake up the rock

CompositionComposition

ExtrusiveExtrusive- Formed from lava; volcanic- Formed from lava; volcanic

IntrusiveIntrusive- Formed deep within the earth- Formed deep within the earth

Obsidian Pumice

Granite

TexturesTextures GlassyGlassy

Fine-grainedFine-grained

Coarse-grainedCoarse-grained

PorphyriticPorphyritic

Obsidian Granite

Granite

Basalt

Classification of Classification of Sedimentary RocksSedimentary Rocks

Clastic Rocks-Clastic Rocks- Made of the Made of the fragments of previously existing fragments of previously existing rocksrocks

Organic Rocks-Organic Rocks- Come from Come from organismsorganisms

Chemical Rocks-Chemical Rocks- Formed by Formed by inorganic processes such as inorganic processes such as evaporationevaporation

Clastics RocksClastics Rocks ConglomerateConglomerate

SandstoneSandstone

MudstoneMudstone

Organic RocksOrganic Rocks

LimestoneLimestone

Coquina Fossiliferous Limestone

Chemical RocksChemical Rocks

LimestoneLimestone

Metamorphic RocksMetamorphic Rocks

Foliated-Foliated- Parallel alignment of flattened Parallel alignment of flattened mineral grains and pebblesmineral grains and pebbles

Unfoliated-Unfoliated-Rocks that are not Rocks that are not banded and do not break into layersbanded and do not break into layers

FoliatedFoliated

Gneisse

UnfoliatedUnfoliated

Marble

Distribution of Rocks in the Distribution of Rocks in the U.S.U.S.