Geology (study of Earth)Geology (study of Earth)

Minerals Minerals RocksRocks Plate TectonicsPlate Tectonics EarthquakesEarthquakes VolcanoesVolcanoes Earth’s History and Fossils (evolution)Earth’s History and Fossils (evolution)

OverviewOverview 33rdrd and 4 and 4thth nine weeksnine weeks

MineralsMinerals

Chapter 3 (orange book)Chapter 3 (orange book)Chapter 4 (green book)Chapter 4 (green book)

A A 1 1 naturally-occurring, naturally-occurring, 2 2 inorganic inorganic 3 3

solid with a solid with a 4 4 definite chemical definite chemical composition.composition.

Study of: MineralogyStudy of: Mineralogy

Branch of: Geology (study of the Earth)Branch of: Geology (study of the Earth)

DefinitionDefinition

Definition/Rules (please consult Definition/Rules (please consult notes)notes)

1.1. If we melted sulfur, would it be a If we melted sulfur, would it be a mineral?mineral?

2.2. If Calcite had a chemical composition If Calcite had a chemical composition of CaCOof CaCO22, would it be a mineral?, would it be a mineral?

3.3. If we made a diamond with PERFECT If we made a diamond with PERFECT cleavage, would it be a mineral?cleavage, would it be a mineral?

4.4. If a fossil had a hardness of 11, would If a fossil had a hardness of 11, would it still be considered a mineral?it still be considered a mineral?

How many known minerals are How many known minerals are there?there?2000?2000?3000?3000?4000?4000?6000?6000?4,9004,900 known mineral species – according to known mineral species – according to wikipedia.comwikipedia.com4,3494,349 Total Valid Species Total Valid Species - International Mineralogy - International Mineralogy AssociationAssociation6,293.6,293. The official list of mineral names, updated in The official list of mineral names, updated in 2009, comprises 6,293 minerals. This list, published by 2009, comprises 6,293 minerals. This list, published by the Commission on New Minerals Nomenclature and the Commission on New Minerals Nomenclature and Classification (CNMNC), includes not only approved Classification (CNMNC), includes not only approved minerals, but also hypothetical, questionable, discredited minerals, but also hypothetical, questionable, discredited and unofficial minerals. The number of known minerals and unofficial minerals. The number of known minerals grows every year ‘“ according to a CNMNC annual grows every year ‘“ according to a CNMNC annual report, about 60 new-mineral proposals are analysed report, about 60 new-mineral proposals are analysed each year.each year.

Over 3000 identified minerals (according to textbook)Over 3000 identified minerals (according to textbook)

Made of elements, which can be found on the periodic Made of elements, which can be found on the periodic table - pg. 61. table - pg. 61.

Example: Example: 1. Silicates are made of silicon 1. Silicates are made of silicon

and oxygen, chemical formula of SiOand oxygen, chemical formula of SiO22

2. Halite made of sodium and 2. Halite made of sodium and Chlorine, chemical formula NaClChlorine, chemical formula NaCl3. Pure elements – sulfur, 3. Pure elements – sulfur,

copper, gold, copper, gold, silver, etc.silver, etc.

Minerals make up rocksMinerals make up rocks Example: Granite is made of quartz, mica and Example: Granite is made of quartz, mica and

feldsparfeldspar

How many minerals exist on Earth?How many minerals exist on Earth? How many “common” minerals are How many “common” minerals are

found on Earth?found on Earth? What four characteristics do all What four characteristics do all

minerals share?minerals share? What are minerals made of? What are minerals made of? What do minerals combine to form?What do minerals combine to form?

Let’s look at the three groups of Let’s look at the three groups of minerals…minerals…

Let’s Review what we Let’s Review what we know…know…

Groups of Minerals – open to page 88Groups of Minerals – open to page 88

SilicatesSilicates: minerals made ofSilicon & : minerals made ofSilicon & Oxygen(SiOOxygen(SiO22))

Quartz - SiOQuartz - SiO22 Feldspar - Feldspar - KAlSiKAlSi33OO88 Anthophyllite - (Mg,Fe)Anthophyllite - (Mg,Fe)77SiSi88OO2222(OH)(OH)22

1.1.CarbonatesCarbonates: Carbonate minerals are : Carbonate minerals are those minerals containing the carbonate ion: COthose minerals containing the carbonate ion: CO33

1.1. CalciteCalcite2.2. DolomiteDolomite

2.2.EvaporitesEvaporites: Minerals that are formed from : Minerals that are formed from ions in solution being left behind as water ions in solution being left behind as water evaporatedevaporated

1.1. HaliteHalite2.2. GypsumGypsum

What two elements are most What two elements are most common in the Earth’s crust?common in the Earth’s crust?

Therefore, what mineral family Therefore, what mineral family do you think is most abundant?do you think is most abundant?

What two minerals do you What two minerals do you think are two of the most think are two of the most common in the Earth’s crust? common in the Earth’s crust?

Tables at bottom of page 88Tables at bottom of page 88

Written Lab ReportWritten Lab Report Introduction & ConclusionIntroduction & Conclusion For each station:For each station:

Define the physical, chemical or special property Define the physical, chemical or special property from that stationfrom that station

Describe procedure you used and lab equipment Describe procedure you used and lab equipment at that stationat that station

Describe very specific results – data table if Describe very specific results – data table if necessarynecessary

Address questions from Standard Lab ReportAddress questions from Standard Lab Report

(use it as a skeleton for your report)(use it as a skeleton for your report)

Advanced Lab Report – Advanced Lab Report –

Purpose: We will be identifying minerals by testing Purpose: We will be identifying minerals by testing minerals’ physical propertiesminerals’ physical properties

We will also be using:We will also be using: ObservationsObservations Chemical Properties Chemical Properties Special PropertiesSpecial Properties

Subjective – opinion, sometimes difficult to classify.Subjective – opinion, sometimes difficult to classify. Objective – numeric – can not be arguedObjective – numeric – can not be argued

Mineral ID Lab – Mineral ID Lab –

1. Color - unreliable in identifying minerals1. Color - unreliable in identifying minerals

*Observation/Appearance is often times *Observation/Appearance is often times NOT enough to identify a mineral – we NOT enough to identify a mineral – we need to test other physical properties.need to test other physical properties.

Physical PropertiesPhysical Properties

(1.) (1.) Color – reliable?Color – reliable?Calcite Calcite

See why testing other physical/chemical properties is necessary!

PyritePyrite

Nearly 300 color variations of diamonds!Nearly 300 color variations of diamonds!

In a select few In a select few minerals, such as minerals, such as sulfur and olivine, sulfur and olivine, color IS a reliable color IS a reliable indicator.indicator.

Reliable colorsReliable colors

Two main types of luster:Two main types of luster:

1. Metallic – looks shiny1. Metallic – looks shiny 2. Nonmetallic2. Nonmetallic

Dull, Earthy, Pearly,Dull, Earthy, Pearly,Vitreous, Gumdrop,Vitreous, Gumdrop,Glassy, Silky, Resinous,Glassy, Silky, Resinous,Greasy/OilyGreasy/Oily

(2.)(2.)Luster- the way a Luster- the way a mineral reflects lightmineral reflects light

The color of a mineral in powder formThe color of a mineral in powder form We use an unglazed porcelain plate We use an unglazed porcelain plate

to test for streakto test for streak What if the mineral shows no streak?What if the mineral shows no streak? More reliable or less reliable than More reliable or less reliable than

color?color?

Be able to name minerals that display Be able to name minerals that display the same, and different color/streak the same, and different color/streak combinations.combinations.

(3.) (3.) StreakStreak

How easily a mineral can be How easily a mineral can be scratchedscratched

Whose hardness scale did we use?Whose hardness scale did we use?

Moh’s Scale of hardness – pg. 91Moh’s Scale of hardness – pg. 91

Hardest and softest?Hardest and softest?

We will use: We will use: Fingernail - 2.5Fingernail - 2.5 Glass - 5.5Glass - 5.5 Streak plate – 6.5Streak plate – 6.5

(4.) (4.) Hardness Hardness

Determined by internal, atomic arrangementDetermined by internal, atomic arrangement Cleavage - to break along a flat surfaceCleavage - to break along a flat surface

Fracture - to break along a jagged surfaceFracture - to break along a jagged surface

Can a mineral have both?Can a mineral have both?

(5.) (5.) Cleavage and Cleavage and FractureFracture

Cleavage

FractureFracture

Conchoidal fracture is a curved breakage

Calcite (CaCOCalcite (CaCO33) reacts with hydrochloric ) reacts with hydrochloric Acid HCl (lower case L, not an i) Acid HCl (lower case L, not an i)

CaCOCaCO33 + HCl ---> CO + HCl ---> CO22 + H + H22OO

Actual: CaCOActual: CaCO3(s)3(s) + 2 HCl + 2 HCl(l)(l) → CaCl → CaCl2(l)2(l) + CO + CO2(g)2(g) + H + H22OO(l)(l)

Reaction shown by “effervescence”Reaction shown by “effervescence” Example of a chemical propertyExample of a chemical property Safety procedures necessary at this stationSafety procedures necessary at this station

(6.) (6.) Acid test – identifying Acid test – identifying CarbonatesCarbonates

EffervescenceEffervescence

Specific gravitySpecific gravity is the ratio of the density of is the ratio of the density of a substance to the density of watera substance to the density of water

Density = mass/volumeDensity = mass/volume Density of a solid: grams/cmDensity of a solid: grams/cm33

Density of a liquid: grams/mLDensity of a liquid: grams/mL

1 cm1 cm33 = 1 mL = 1 mL

Specific Gravity of 19.28 means it is 19.28 Specific Gravity of 19.28 means it is 19.28 times more dense than the same volume of times more dense than the same volume of water.water.

(7.) (7.) Specific GravitySpecific Gravity

Taste – HaliteTaste – Halite Odor – sulfurOdor – sulfur Magnetism – magnetiteMagnetism – magnetite Double refraction – Icelandic Spar Double refraction – Icelandic Spar

CalciteCalcite Fluorescence Fluorescence Effervescence –carbonates (calcite & Effervescence –carbonates (calcite &

dolomite)dolomite)

Special Properties – Special Properties – pg. 94pg. 94

Double RefractionDouble Refraction

FluorescenceFluorescence

In minerals formed from magma, crystal In minerals formed from magma, crystal size indicates the speed the magma/lava size indicates the speed the magma/lava cooled (solidified).cooled (solidified).

Large crystals – slowlyLarge crystals – slowly

Small crystals – quicklySmall crystals – quickly

No crystals – very quicklyNo crystals – very quickly

Crystal SizeCrystal Size

Hydrochloric Acid Hydrochloric Acid Use one drop of HClUse one drop of HCl Goggles are mandatoryGoggles are mandatory Clean minerals after useClean minerals after use Keep station clean/dryKeep station clean/dry

Hardness station - glass plate remains Hardness station - glass plate remains on lab on lab tabletable

No licking minerals at any other station than No licking minerals at any other station than “taste”. Wash minerals when you’re done. “taste”. Wash minerals when you’re done.

Pick up and replace ONE mineral at a timePick up and replace ONE mineral at a time

Lab SafetyLab Safety

Diamond - hardest mineralDiamond - hardest mineral Talc - 1 on MohTalc - 1 on Moh’’s scales scale Sulfur - example of odor & reliable colorSulfur - example of odor & reliable color Calcite - reacts with HClCalcite - reacts with HCl Halite - (NaCl) tasteHalite - (NaCl) taste Pyrite - (foolPyrite - (fool’’s gold) color/streaks gold) color/streak Magnetite - displays magnetic Magnetite - displays magnetic

characteristicscharacteristics Icelandic Spar Calcite – Double Icelandic Spar Calcite – Double

RefractionRefraction Your birthstoneYour birthstone

Know these minerals!!!Know these minerals!!!

Mine the oreMine the oreA mineral is an ore if it can A mineral is an ore if it can be mined at a profitbe mined at a profit

Processed and sometimes Processed and sometimes smeltedsmelted

Refine and purify the oreRefine and purify the ore Gems often need Gems often need

cut/polishedcut/polished

How do we get and use How do we get and use Minerals?Minerals?

To melt (ore) in order to separate the To melt (ore) in order to separate the metal containedmetal contained

The ore and the valuable mineral must The ore and the valuable mineral must have different melting temperatureshave different melting temperatures

SmeltingSmelting

Do not confuse smelting with smelting Do not confuse smelting with smelting (catching small fish called smelt)(catching small fish called smelt)

SmeltingSmelting

Rare and beautiful Rare and beautiful mineralsminerals Special varieties of another mineralSpecial varieties of another mineral Examples of gems and their common Examples of gems and their common

mineral forms are:mineral forms are: Topaz --> TopazTopaz --> Topaz Ruby --> SpinelRuby --> Spinel Emerald --> BerylEmerald --> Beryl Sapphire --> QuartzSapphire --> Quartz Amethyst--> QuartzAmethyst--> Quartz

Gems or gemstonesGems or gemstones

Semiprecious Minerals – garnet, Semiprecious Minerals – garnet, tanzanite, fine tourmaline, spinel, and tanzanite, fine tourmaline, spinel, and aquamarine, aquamarine,

Precious Minerals: Precious Minerals: diamond, ruby, sapphire diamond, ruby, sapphire and emerald, (pearl) and emerald, (pearl) (amethyst)(amethyst)

Diamonds - cutting, saw blades, drill bitsDiamonds - cutting, saw blades, drill bits Quartz – electronics, time pieces, computers, Quartz – electronics, time pieces, computers,

semiprecious gemstonesemiprecious gemstone Gems - jewelry, valuableGems - jewelry, valuable Some ore minerals often contain valuable Some ore minerals often contain valuable

elements elements From these minerals we get aluminum, From these minerals we get aluminum,

titanium, zinc, etc.titanium, zinc, etc. Graphite - pencils, lubricantGraphite - pencils, lubricant Gypsum - wallboard, cementGypsum - wallboard, cement Sulfur – fireworks, weaponsSulfur – fireworks, weapons

Uses of minerals and Uses of minerals and gemsgems

Corundum – used for abrasivesCorundum – used for abrasives Bauxite – aluminum oreBauxite – aluminum ore Halite – food seasoning and Halite – food seasoning and

preservationpreservation Talc – paper, ceramicsTalc – paper, ceramics

Other Uses for Other Uses for MineralsMinerals

A diamond will leave a WHITE streak on a A diamond will leave a WHITE streak on a streak plate. streak plate.

A gem is A gem is plentifulplentiful and and uglyugly!! The streak plate we used in class is a The streak plate we used in class is a

glazed porcelain plateglazed porcelain plate Since gypsum has large crystals, it Since gypsum has large crystals, it

probably formed by cooling slowly.probably formed by cooling slowly. A mineral is always organic.A mineral is always organic.

Review: Review: The formula for the The formula for the calcite reactioncalcite reaction Native mineralsNative minerals– what are these?– what are these?

True or FalseTrue or False