rocks and minerals ms. sanderson. what is the difference between a rock and a mineral? minerals:...
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Rocks and MineralsRocks and Minerals
Ms. SandersonMs. Sanderson
What is the difference between What is the difference between a Rock and a Mineral?a Rock and a Mineral?
Minerals: Minerals: – Naturally occurringNaturally occurring– InorganicInorganic– SolidSolid– Definite chemical Definite chemical
structure (4000 structure (4000 known to man)known to man)
Rock: made up of Rock: made up of minerals minerals (aggregates (aggregates mixture)mixture)
MineralsMinerals
The The buildingbuilding blocks of blocks of mineralsminerals are are elementselements
ELEMENTSELEMENTSThe Building blocks for minerals.The Building blocks for minerals.Is a Is a substancesubstance that that cannotcannot be be
broken down into broken down into simplersimpler substances by substances by chemicalchemical or or physicalphysical meansmeans
Organized by their properties in the Organized by their properties in the Periodic TablePeriodic Table
PERIODIC TABLEPERIODIC TABLE
MOST COMMON MOST COMMON ELEMENTS ON CRUST OF ELEMENTS ON CRUST OF
EARTHEARTHOxygenOxygen46.6%46.6%SiliconSilicon 27.7 % 27.7 %Aluminum Aluminum 8.1 % 8.1 %IronIron 5% 5%CalciumCalciumSodiumSodiumPotassiumPotassiumMagnesiumMagnesium
ATOMSATOMSAre the Are the smallest smallest particle of particle of mattermatter that that
contains the characteristics of an contains the characteristics of an elementelement..
Parts of an Atom:Parts of an Atom:NucleusNucleus Central region of the atom.Central region of the atom.
– Contains Contains ProtonsProtons and and NeutronsNeutronsEnergy LevelsEnergy Levels area where electrons area where electrons
traveltravel
ProtonsProtons
Positively charged “+” subatomic Positively charged “+” subatomic particleparticle
Found in the nucleusFound in the nucleus The atomic number of the elementThe atomic number of the element
NeutronsNeutrons
Neutrally charged subatomic Neutrally charged subatomic particleparticle
Found in the nucleusFound in the nucleus Same mass as a protonSame mass as a proton
ElectronsElectrons
Smallest part of an atomSmallest part of an atom Negatively charged “—” subatomic Negatively charged “—” subatomic
particleparticle Found in the energy levels Found in the energy levels
surrounding the nucleussurrounding the nucleus Located in regions called Located in regions called Energy Energy
LevelsLevels which surround the nucleus which surround the nucleus
ISOTOPESISOTOPES
Atoms with the Atoms with the same number of same number of protons but protons but different number different number of neutronsof neutrons– Neutron Neutron
changechange
BONDSBONDS Compounds:Compounds: Is a substance that consists of two Is a substance that consists of two
or more elements that are chemically combined in or more elements that are chemically combined in specific proportions.specific proportions.
Chemical Bond:Chemical Bond: forces that hold atoms together forces that hold atoms together in a compoundin a compound
Three Types of BondsThree Types of Bonds– IonicIonic– CovalentCovalent– MetallicMetallic
Ionic and Covalent Ionic and Covalent BondsBonds
IonicIonic Atoms gain or lose Atoms gain or lose
electrons (transfer of electrons (transfer of electrons)electrons)
Between a metal and Between a metal and nonmetalnonmetal
EX: salts, calcium fluorideEX: salts, calcium fluoride
CovalentCovalent Form when atoms Form when atoms
share electrons.share electrons. Between Nonmetal Between Nonmetal
and Nonmetaland Nonmetal Ex: Water, diamondEx: Water, diamond
METALLIC BONDSMETALLIC BONDS Form when electrons are shared by metal ions.Form when electrons are shared by metal ions. Metals are malleable, ductile and conductors.Metals are malleable, ductile and conductors. Between Metal and MetalBetween Metal and Metal Sharing of electron pool give metals their Sharing of electron pool give metals their
propertiesproperties
How Minerals FormHow Minerals Form
Four WaysFour Ways– Crystallization from magmaCrystallization from magma– PrecipitationPrecipitation– Changes in Pressure and TemperatureChanges in Pressure and Temperature– Hydrothermal SolutionsHydrothermal Solutions
Crystallization from MagmaCrystallization from Magma
As magma cools, elements combine As magma cools, elements combine to form minerals.to form minerals.
Crystal structure depends on rate of Crystal structure depends on rate of cooling and pressurecooling and pressure
First to Crystallize:First to Crystallize: minerals rich minerals rich in iron, calcium and magnesiumin iron, calcium and magnesium
Precipitation Precipitation
Water evaporates, some dissolved Water evaporates, some dissolved substances can react to form substances can react to form mineralsminerals
When minerals are dissolved out of a liquid.When minerals are dissolved out of a liquid. Through evaporation or temperature change of Through evaporation or temperature change of
water. water. ExamplesExamples
– CalciteCalcite– HaliteHalite
Pressure and TemperaturePressure and Temperature
An increase of An increase of pressurepressure can cause a can cause a mineral to recrystallize while still mineral to recrystallize while still solidsolid
Changes in Changes in temperaturetemperature can also can also cause certain minerals to become cause certain minerals to become unstable and recrystallize to form a unstable and recrystallize to form a new mineral that is stable at the new new mineral that is stable at the new temperature.temperature.
Examples: talc and muscoviteExamples: talc and muscovite
Hydrothermal SolutionsHydrothermal Solutions
Very hot mixture of water and Very hot mixture of water and dissolved substancedissolved substance
When these solutions come into When these solutions come into contact with existing minerals, contact with existing minerals, chemical reactions take place to form chemical reactions take place to form new minerals.new minerals.
Examples:Examples:– QuartzQuartz– PyritePyrite
Mineral GroupsMineral Groups
Over 3800 minerals have been namedOver 3800 minerals have been named Minerals are classified into groups Minerals are classified into groups
based on their compositionbased on their composition– SilicatesSilicates– Sulfides & SulfatesSulfides & Sulfates– HalidesHalides– CarbonatesCarbonates– OxidesOxides– Native ElementsNative Elements
SilicatesSilicates
Most common group on EarthMost common group on Earth Silicon and Oxygen combine to form a Silicon and Oxygen combine to form a
structure called the silicon-oxygen structure called the silicon-oxygen tetrahedrontetrahedron
Two most abundant elements are Two most abundant elements are SILICON AND OXYGENSILICON AND OXYGEN
EX: QuartzEX: Quartz
AugiteAugite
MicasMicas
CarbonatesCarbonates
Second most common mineral Second most common mineral group.group.
Contains the element carbon, Contains the element carbon, oxygen and one or more other oxygen and one or more other metallic elementsmetallic elements
Ex: Ex: – CalciteCalcite– DolomiteDolomite
OxidesOxides
Minerals that Minerals that contain oxygen contain oxygen and one or more and one or more other elements, other elements, which are usually which are usually metalsmetals
Ex:Ex:– RutileRutile– CorundumCorundum– HematiteHematite
Sulfides & SulfatesSulfides & Sulfates
Contains the Contains the element sulfur & element sulfur & other elementsother elements
Ex:Ex:– GypsumGypsum– GalenaGalena– Pyrite Pyrite
HalidesHalides
Contains a halogen Contains a halogen ion plus one or ion plus one or more other more other elements.elements.
Elements from Elements from Group 7A on the Group 7A on the periodic table-- like periodic table-- like fluorine and fluorine and chlorine. chlorine.
Ex:Ex:– HaliteHalite– FluoriteFluorite
Native ElementsNative Elements
Group of minerals Group of minerals that exist in that exist in relatively pure relatively pure formform
Ex:Ex:– GoldGold– SilverSilver– CopperCopper– SulfurSulfur– CarbonCarbon
Properties of Minerals—used to Properties of Minerals—used to identify mineralsidentify minerals
StreakStreak ColorColor LusterLuster Crystal FormCrystal Form Hardness ScaleHardness Scale CleavageCleavage
FractureFracture DensityDensity TextureTexture MagneticMagnetic ConductorConductor Reaction with AcidReaction with Acid
ColorColor
Not a useful tool for identificationNot a useful tool for identification Small amount of different elements Small amount of different elements
can give the same mineral different can give the same mineral different colorscolors
Olivine = greenish tintOlivine = greenish tint
StreakStreak
The color of a mineral in its The color of a mineral in its powdered form.powdered form.
Found by rubbing mineral across a Found by rubbing mineral across a streak plate.streak plate.
Example: Galena (below) using an Example: Galena (below) using an unglazed porcelain tileunglazed porcelain tile
LusterLuster How light is reflected from the surface of a How light is reflected from the surface of a
mineral (how shiny it is)mineral (how shiny it is) Two types: Metallic: looks like a metal & Two types: Metallic: looks like a metal &
Nonmetallic: does not look like a metalNonmetallic: does not look like a metal
Crystal FormCrystal Form
Visible expression of Visible expression of minerals internal minerals internal arrangement of atomsarrangement of atoms
Structure of the mineralsStructure of the minerals Size depends on the length Size depends on the length
exposed to heat exposed to heat
HardnessHardness
A measure of the A measure of the resistance of a resistance of a mineral to being mineral to being scratchedscratched
Measured on Mohs Measured on Mohs Hardness scaleHardness scale
10 minerals 10 minerals arranged from 10 arranged from 10 (hardest) to 1 (hardest) to 1 (softest)(softest)
Finger NailFinger Nail2.52.5Copper pennyCopper penny
3.53.5GlassGlass 5.5 5.5Streak PlateStreak Plate
6.56.5
CleavageCleavage
Tendency of a mineral to break along Tendency of a mineral to break along flat even planes.flat even planes.
Micas show the simplest type of Micas show the simplest type of cleavage.cleavage.
FractureFracture
The uneven breakage of a mineralThe uneven breakage of a mineral If a mineral does not have cleavage If a mineral does not have cleavage
then it has fracturethen it has fracture
Density Density
The ratio of an objects mass to its volume.The ratio of an objects mass to its volume. Each mineral has its own unique densityEach mineral has its own unique density Density of Gold is 19.3 g/cm^3Density of Gold is 19.3 g/cm^3
Other:Other:
Texture (soapy, greasy)Texture (soapy, greasy) Magnetism (attraction to a magnet)Magnetism (attraction to a magnet) Smell (sulfur smells like a rotten egg)Smell (sulfur smells like a rotten egg) Reaction to acid (mineral fizzes)Reaction to acid (mineral fizzes)
Double RefractionsDouble Refractions– When a piece of transparent calcite is placed When a piece of transparent calcite is placed
over printed material, the letters appear over printed material, the letters appear doubled.doubled.
TextureTexture MagneticMagnetic
What does it feels What does it feels like.like.
Mica - brittle Mica - brittle Talc - soapyTalc - soapy
Attracted or Attracted or repelled by a repelled by a magnet.magnet.
Example: Example: MagnetiteMagnetite
ConductorConductor Rxn with Acid Rxn with Acid
Does it conduct Does it conduct electricity?electricity?
Does it fizz in acid?Does it fizz in acid? Mostly tested with Mostly tested with
HCL. Calcite below:HCL. Calcite below:
What is a ROCK?What is a ROCK?
Any solid mass of mineral or mineral-Any solid mass of mineral or mineral-like matter that occurs naturally as like matter that occurs naturally as part of our planetpart of our planet
Three types of rock:Three types of rock:
1.1. Igneous Igneous
2.2. SedimentarySedimentary
3.3. MetamorphicMetamorphic
The Rock CycleThe Rock Cycle
Interaction among Earths water, air, Interaction among Earths water, air, land, and living things can cause land, and living things can cause rocks to change from one type to rocks to change from one type to anotheranother
A continuous processA continuous process
Igneous RocksIgneous Rocks
Form when magma or lava hardensForm when magma or lava hardens
LAVA vs. MAGMALAVA vs. MAGMA
LavaLavaMolten rock Molten rock
on the on the surface of surface of EarthEarth
MagmaMagmaMolten rock Molten rock
beneath beneath Earth’s surfaceEarth’s surface
Formation of Igneous RocksFormation of Igneous Rocks
Intrusive Igneous Intrusive Igneous RocksRocks
Rocks that form Rocks that form when magma when magma hardens beneath hardens beneath Earth’s surfaceEarth’s surface
EX: GraniteEX: Granite
Extrusive Igneous Extrusive Igneous RocksRocks
Rocks that form Rocks that form when lava when lava hardens on the hardens on the surface of the surface of the Earth Earth
EX: RhyoliteEX: Rhyolite
Classification of Igneous RocksClassification of Igneous Rocks
Texture & composition are two Texture & composition are two characteristics used to classify characteristics used to classify igneous rocks.igneous rocks.
Classification of Igneous RocksClassification of Igneous Rocks
TextureTexture=size, =size, shape, and shape, and arrangement of arrangement of interlocking interlocking crystalscrystals
OBSIDIAN-EXTRUSIVE
TextureTexture
Coarse-GrainedCoarse-Grained Slow cooling Slow cooling Large crystalsLarge crystals
Fine-GrainedFine-Grained Rapid cooling of Rapid cooling of
magma or lavamagma or lava Small, Small,
interconnected interconnected mineral grains mineral grains
Peridotite
IntrustiveAndesite--extrusive
TextureTexture
GlassyGlassy Extrusive Igneous Extrusive Igneous
RockRock Looks like glassLooks like glass
PorphyriticPorphyritic Large crystals Large crystals
embedded in a embedded in a matrix of much matrix of much smaller crystalssmaller crystals
Porphyritic Andesite-extrusive
Obsidian--extrusive
CompositionComposition
CompositionComposition=Based on =Based on proportions of light and dark proportions of light and dark mineralsminerals
TypesTypes– GraniticGranitic– BasalticBasaltic– Andesitic Andesitic – UltramaficUltramafic
CompositionComposition
Basaltic Basaltic Contains many dark silicate minerals and Contains many dark silicate minerals and
plagioclase feldsparplagioclase feldspar Rich in magnesium & ironRich in magnesium & iron Example: basalt & gabbroExample: basalt & gabbro
CompositionComposition
GraniticGranitic Made almost entirely of light-colored Made almost entirely of light-colored
silicate minerals like quartz and silicate minerals like quartz and feldsparfeldspar
0 to 25% dark minerals0 to 25% dark minerals Example: biotite & amphiboleExample: biotite & amphibole
Other CompositionOther Composition
AndesiticAndesitic Between granitic and basalticBetween granitic and basaltic At least 25% dark mineralsAt least 25% dark minerals
CompositionComposition
UltramaficUltramafic Composed mainly of iron and Composed mainly of iron and
magnesium-rich mineralsmagnesium-rich minerals Almost entirely dark mineralsAlmost entirely dark minerals
Comp/Comp/
TextureTextureGranitGranitee
AndesiticAndesitic BasalticBasaltic UltramaficUltramafic
CoarseCoarse GraniteGranite DioriteDiorite GabbroGabbro PeriodtitePeriodtite
FineFine PhyolitePhyolite AndesiteAndesite BasaltBasalt KematiteKematite
PorphyriticPorphyritic Inside any given rockInside any given rock UncommonUncommon
GlassyGlassy Obsidian, PumiceObsidian, Pumice
What is a Sedimentary Rock?What is a Sedimentary Rock?
Forms when Forms when existing rocks are existing rocks are broken down into broken down into sediment then sediment then compacted and compacted and cemented togethercemented together
Formation of Sedimentary RockFormation of Sedimentary Rock
InvolvesInvolves
– WeatheringWeathering is the next step—any is the next step—any process that breaks rocks into sediment.process that breaks rocks into sediment.
– ErosionErosion– the removal of weathered – the removal of weathered rocksrocks
Formation of Sedimentary RocksFormation of Sedimentary Rocks
– DepositionDeposition-- When the agents of -- When the agents of erosion (wind, water, ice or gravity) erosion (wind, water, ice or gravity) loses energy, it drops the sediment.loses energy, it drops the sediment.
– CompactionCompaction—process that squeezes or —process that squeezes or compacts sediment togethercompacts sediment together
– CementationCementation takes place when takes place when dissolved minerals are deposited in the dissolved minerals are deposited in the tiny spaces among the sedimenttiny spaces among the sediment
Classification of Sedimentary RockClassification of Sedimentary Rock
Classified into two Classified into two main groups main groups according to the according to the way they form.way they form.– Either Clastic or Either Clastic or
ChemicalChemical
Rock Salt
Chemical
Clastic Sedimentary RockClastic Sedimentary Rock
Made of weathered Made of weathered bits of rocks & bits of rocks & mineralsminerals
Grouped according Grouped according to size of the to size of the sedimentssediments
Conglomerate
Clastic
Grain sizeGrain size Sediment Sediment NameName
Rock NameRock Name
Coarse (over Coarse (over 2mm in size)2mm in size)
Gravel-roundedGravel-rounded ConglomerateConglomerate
Gravel-angularGravel-angular BrecciaBreccia
Medium (2mm Medium (2mm to 1/6 mm)to 1/6 mm)
SandSand SandstoneSandstone
Fine (1/16 to Fine (1/16 to 1/256 mm)1/256 mm)
SiltSilt SiltstoneSiltstone
Very fine (less Very fine (less than 1/256 than 1/256 mm)mm)
MudMud Shale/mudstoneShale/mudstone
Chemical Sedimentary RockChemical Sedimentary Rock
Form when dissolved minerals Form when dissolved minerals precipitate from water solutionprecipitate from water solution(Rock salt and flint)(Rock salt and flint)
Biochemical Sedimentary RocksBiochemical Sedimentary Rocks– Made from once living organisms like Made from once living organisms like
shells and skeleton remainsshells and skeleton remains– Ex: Chalk, Limestone, rock saltEx: Chalk, Limestone, rock salt
CompositionComposition TextureTexture Rock NameRock Name
CalciteCalcite Fine to coarseFine to coarse
Visible shellsVisible shells
Small shells Small shells and clayand clay
LimestoneLimestone
CoquinaCoquina
ChalkChalk
QuartzQuartz Very fineVery fine Chert (light Chert (light colored)colored)
Flint (dark Flint (dark colored)colored)
GypsumGypsum Fine to coarseFine to coarse Rock GypsumRock Gypsum
HaliteHalite Fine to coarseFine to coarse Rock SaltRock Salt
Altered plant Altered plant fragmentsfragments
Fine-grained Fine-grained organic matterorganic matter
CoalCoal
What is a Metamorphic RockWhat is a Metamorphic Rock
Form when existing Form when existing rocks are changed rocks are changed by heat and by heat and pressurepressure
Metamorphism—Metamorphism—means “change means “change form”form”
Agents of MetamorphismAgents of Metamorphism
The agents of metamorphism areThe agents of metamorphism are– HeatHeat provides the energy provides the energy
needed to drive chemical needed to drive chemical reactions which causes existing reactions which causes existing minerals to recrystallize.minerals to recrystallize.
Agents of MetamorphismAgents of Metamorphism
– PressurePressure applied in all directions applied in all directions on a rock which causes spaces on a rock which causes spaces between grains to closebetween grains to close
– Hydrothermal solutionsHydrothermal solutions hot, hot, water solution that promote water solution that promote recrystallization by dissolving recrystallization by dissolving original minerals & then depositing original minerals & then depositing new onesnew ones
Classification of Metamorphic Classification of Metamorphic RocksRocks
Classified by Classified by texture & texture & compositioncomposition
– TextureTexture FoliatedFoliated Non-foliatedNon-foliated
– CompositionComposition
Greenstone
Non-foliated
Foliated Metamorphic RocksFoliated Metamorphic Rocks
A rock with layered or A rock with layered or banded appearance banded appearance that had been that had been metamorphosed metamorphosed
Example: GneissExample: Gneiss Four Main TypesFour Main Types
– SlateSlate– PhyllitePhyllite– SchistSchist– GneissGneiss
Gneiss
SlateSlate
PhyllitePhyllite
SchistSchist
GneissGneiss
Non-foliated Metamorphic Non-foliated Metamorphic RocksRocks
Does not have a Does not have a banded texturebanded texture
Contains only one Contains only one mineralmineral
Ex: MarbleEx: Marble– Calcite crystalsCalcite crystals
Quartzite—made from QuartzQuartzite—made from Quartz
Anthracite—made of CoalAnthracite—made of Coal
Rock Rock NameName
TextureTexture Grain Grain SizeSize
Parent Parent RockRock
SlateSlate foliatedfoliated Very fineVery fine Shale, Shale, mudstone, or mudstone, or
siltstonesiltstone
PhyllitePhyllite foliatedfoliated FineFine SlateSlate
SchistSchist foliatedfoliated Medium to Medium to coarsecoarse
PhyllitePhyllite
GneissGneiss foliatedfoliated Medium to Medium to coarsecoarse
Schist, phyllite, Schist, phyllite, or volcanic or volcanic
rocksrocks
MarbleMarble Non-Non-foliatedfoliated
Medium to Medium to coarsecoarse
Limestone, Limestone, dolostonedolostone
QuartziteQuartzite Non-Non-foliatedfoliated
Medium to Medium to coarsecoarse
Quartz Quartz sandstonesandstone
AnthraciteAnthracite Non-Non-foliatedfoliated
finefine CoalCoal