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Building a House Out of Minerals
A roof is a barrier to snowand rain. What mineral is used in clay singles to cover the plywood sheets on the roof?
___________________
Cement is used for the foundation and chimneyof a house. Cement contains this mineralwhich is a source of calcium.
___________________
Exterior walls can be made of things such as aluminum or steel siding or brick. What is one mineral that could be found in aluminum siding? ___________________
Windows let in visible light and allow us to see outside. What clear mineral is used to make window glass? ___________________Electrical wiring conducts electricity
most wiring in made of metal. What mineral is often used for wiring? ___________________
Metal pipes are commonly used to carry fresh water into the house. In the 1950’s a poisonous mineral was used in plumbing, what was it? ___________________
Interior walls shape the rooms in a house. The wallboard covers the walls and is soft so that holes can be drilled in it for outlets and nails can be used to hang pictures. What mineral is wallboard made of? ___________________
Word Bank: Aluminum, Lead, Gypsum, Copper, Quartz, Illite (clay), Calcite
The Star of Bombay
182-carat star sapphire
Minerals versus Rocks
Composition and Structure of Minerals
Properties of Minerals
Mineral Groups
Mineral Resources
Minerals Versus RocksMinerals Versus Rocks
• A rock is an aggregate of minerals
• Minerals are the building blocks that make up rocks
Varieties of MineralsVarieties of Minerals
Quartz Olivine (Peridot)
Beryl (aquamarine) Native Copper
More than
3000
different
minerals
Definition of MineralDefinition of Mineral• Naturally occurring• Solid• Inorganic (never living)• Definite chemical composition• Orderly internal structure of atoms
Cubic
Tetragonal
Hexagonal
Chemical Chemical formula:formula:
CCChemical formula:
C
Graphite Diamond
How can 2 minerals with the same composition be so different?
What’s the point here?
“Internal Arrangement of Atoms” controls most physical properties!
Mineral FormationMineral Formation
1. Cooling of magma-molten rock beneath the earth’s surface
– if it cools fast small crystals– if it cools slowly large crystals
2. Compounds dissolved in a liquid (water); liquid evaporates & leaves behind crystals
• Most minerals made up of only 8 elements these 8 elements make up 98% of Earth’s crust
Relative abundance of the most common elements in the Earth’s crust
Element Approximate Percentage by Weight
Oxygen (O) 46.6%
Silicon (Si) 27.7%
Aluminum (Al) 8.1%
Iron (Fe) 5.0%
Calcium (Ca) 3.6%
Sodium (Na) 2.8%
Potassium (K) 2.6%
Magnesium (Mg) 2.1%
All Others 1.7%Total 100%
Mineral GroupsMineral Groups– Silicates: contains silicon + oxygen + one or
more other elements (Most common rock forming minerals are silicates)
– Carbonates: 1 carbon + 3 oxygen + other elements
– Oxides: 2 oxygen + other elements– Sulfides: sulfur + other elements– Sulfates: 1 sulfur + 4 oxygen + other elements– Halides: chlorine, fluorine, bromine, or Iodine
+ other elements– Native elements: elements that are
uncombined
QuartzQuartz Mica
KAl2(AlSi3O10)(OH,F,Cl)2SiO2
Can you find the “silica” ?
Silicates
Silica StructureSilica Structure
4 oxygen atoms for every 1 silicon atom
CalciteCalcite
Carbonates
Mineral IdentificationMineral Identification
• Hardness
• Color
• Streak Test
• Luster
• Crystal Form
• Cleavage / Fracture
Mineral PropertiesMineral PropertiesHardness - A measure of the resistance of a mineral to abrasion or scratching.
Mohs Hardness ScaleMohs Hardness Scale
Relative Scale Mineral Other ObjectsHardest 10 Diamond
9 Corundum
8 Topaz
7 Quartz
6 K-Feldspar 5.5 Glass, Pocketknife
5 Apatite
4 Fluorite 3.5 Copper Penny
3 Calcite 2.5 Fingernail
2 Gypsum
Softest 1 Talc
Colorless quartz Purple quartz (amethyst)
Brueno Jasper
Mineral PropertiesMineral Properties ColorColor
Mineral PropertiesMineral PropertiesStreak – The color of a mineral in its
powdered form.
The Mineral Hematite Always Has a Red Brown Streak Whether It Is the Metallic or Earthy Variety.
Mineral PropertiesMineral PropertiesLuster – the
appearance or quality of light
reflected from the surface of the
mineral.
• Metallic vs. nonmetallic
• Nonmetallic – vitreous (glassy), pearly, silky,
resinous, and earthy
Amethyst with vitreous luster
Mineral PropertiesMineral PropertiesCrystal form – the
external expression of a mineral’s internal orderly
arrangement of atoms.
Pyrite – Cubic Crystals
Quartz -Hexagonal Quartz -Hexagonal CrystalsCrystals
Quartz -Hexagonal Quartz -Hexagonal CrystalsCrystals
Mineral PropertiesMineral Properties
Cleavage – The tendency of a mineral
to cleave, or break, along planes of weak
bonding.
Simple cleavage in micasMultiple cleavages in
fluorite, halite and calcite
Halite
Fluorite
Calcite
1 plane - Micas2 planes – K Feldspar
3 planes – Halite (salt) 3 planes (rhombo.) - Calcite
Mineral PropertiesMineral Properties
Fracture-Minerals that do not break
along cleavage
planes are said to possess fracture
Conchoidal fracture in quartz
Mineral PropertiesMineral Properties
Specific gravity – compares the
weight of a mineral to the
weight of an equal volume of water.
High specific gravity of galena.
Additional PropertiesAdditional Properties• Effervescence - Calcite and powdered dolomite will
effervesce (fizz) in dilute hydrochloric acid (HCl) • Smell- Sphalerite will give off a rotten-egg smell when
streaked on a streak plate. (Note: pure sulfur does not smell like rotten eggs!)
• Magnetism- Magnetite (AKA Lodestone) will pick up paper clips (weak samples will only be able to pick up staples)
• Taste- Halite is rock salt and will taste salty. *Do not taste the samples since some have been tested with acid to see if it is calcite.
• Fluorescence- some minerals (mostly forms of calcite) will glow in fluorescent colors under a black (UV) light.
• Double refraction- some clear forms of calcite (Iceland Spar) will make a double image of words.
Additional PropertiesAdditional Properties
Fluorescence Double refraction
Uses of MineralsUses of Minerals
• Gems: highly prized minerals because they are rare and beautiful– Most gems are brighter and
more colorful than common samples of minerals
– Ex: Emeralds, rubies, diamonds
– Ex. Amethyst: a form of quartz with traces of iron, sapphires
– Trace amounts of elements can make some gems more rare than others = More money
Uses of MineralsUses of Minerals
• Ores: a mineral is an ore if it contains a useful substance that can be mined for a profit– Ex. Al from bauxite– Fe from hematite– Titanium from rutile
AsbestosAsbestos
• A mineral with threadlike, flexible fibers– Used for insulation and fire
protection = doesn’t burn or conduct heat
– When these fibers become loose and airborne → often get into the lungs where they’ve been known to cause cancer (carcinogen)
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