BAESI: Californias Resources

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BAESI Californias Resources

• Earth Materials

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Earth MaterialsFocus Questions

• Why are Earth materials important?
• What is a mineral?
• Whats the difference between a mineral and a
  rock?

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What is a Mineral?

• A mineral is a naturally-occurring solid
• with a definite (but generally not fixed)
• chemical composition and an orderly
• internal arrangement of atoms (crystalline).

Examples of chemical formulas for
minerals Quartz SiO2 Pyrite FeS2
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Crystalline
Halite - NaCl Definite chemical
composition Orderly arrangement of
atoms
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How Many Minerals Are There?gt 4,000 - but only
a few are common in rocksRelative abundance of
elements in Earths crust
Silicates are most common
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Rocks Aggregates of Minerals
http//www.geo.wvu.edu/jtoro/geol101/minerals/Gra
nitic_Minerals.jpg
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Mineral Identification

• What properties can be used to identify minerals?
• What do you observe?

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Physical properties used to identify minerals

• Color
• Streak
• Luster
• Hardness
• Cleavage/fracture
• Specific gravity (heft)
• Reaction with dilute HCl (or vinegar)
• Magnetism
• Crystal habit or form

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Mohs Scale of Hardness
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Examples of Cleavage
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FORMATION OF MINERAL DEPOSITS
Source Steve Nelson, Tulane Univ.
Concentration factor the increase in
concentration of a mineral required to form an
ore. Is this a constant?
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Types of Mineral Deposits

• Hydrothermal mineral deposits form in association
  with magma and water
• Gold, cinnabar
• Residual mineral deposits formed by weathering
  reactions at the earths surface.
• Bauxite (aluminum ore) in tropical soil
• Placer deposits are sorted and distributed by
  flow of transporting media such as water, wind
  and ice
• Sand and gravel gold, diamonds
• Sedimentary mineral deposits are precipitated
  from a solution, typically sea water (evaporites)
• Salt, borates
• Mineral deposits form in association with
  metamorphism
• Graphite, garnet

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Mineral Resources Overview

• Metallic Minerals
• Non-ferrous Copper, Zinc, Tin, Lead, Aluminum,
  Titanium, Manganese, Magnesium, Mercury,
  Vanadium, Molybdenum, Tungsten, Silver, Gold,
  Platinum
• Energy Resources
• Fossil Fuels Coal, Oil, Natural Gas
• Uranium
• Geothermal Energy

• Building
• Stone, Sand, Gravel, Limestone
• Non-metallic Minerals
• Sulfur, Gypsum, Coal, Barite, Salt, Clay,
  Feldspar, Gem Minerals, Abrasives, Borax, Lime,
  Magnesia, Potash, Phosphates, Silica, Fluorite,
  Asbestos, Mica
• Metallic Minerals
• Ferrous Iron and Steel, Cobalt, Nickel

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Mineral Resources

• Are mineral resources renewable or
• nonrenewable?
• Why?

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http//www.mii.org/images/baby.jpg
http//www.mii.org/images/baby.jpg
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Mineral Resources

• Metals iron, aluminum, copper, lead, zinc,
  nickel, cobalt, gold, silver, or platinum
• Nonmetallic Minerals sulfides, lime (calcium
  carbonate), sulfur, halite, clay, gypsum, or
  potash
• Rock resources most abundant quantity of earth
  resources we use
• Sand, gravel, limestone, quartz-rich sand,
  marble, granite, and sandstone
• Energy Resources
• Fossil Fuels Coal, Oil, Natural Gas
• Uranium
• Geothermal Energy

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Uses for some minerals and rocks

• Hematite
• Quartz
• Graphite
• Gypsum
• Calcite
• Galena

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Minerals Hematite Ore of iron used to make
steel pigment Quartz (silicon dioxide) Primary
ingredient in glass Graphite Pencil lead
lubricant Gypsum Plaster of paris drywall
wallboard Calcite In toothpastes, cements, and
mortars Galena Ore of lead Rocks Obsidian -
Ornamental stone, anciently used as a tool,
jewelry, brain surgery scalpel blade Granite -
Used in buildings Pumice - An abrasive in soaps
and in emery boards. Sandstone - Used in
construction Limestone - Used to manufacture
cement, paper, and the packaging of chewing gum
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Californias Non-fuel Mineral Production, 2007
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Mineral Resources Distribution

• Globally, very un-even distribution
• Some countries have plenty export nations
• Some countries have none import nation
• Un-even distribution wars fought

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World Mineral Supply

• Technology often allows more access to difficult
  or low grade ore deposits
• Less developed nations are striving to achieve
  comparable standards of living as the
  technologically advanced countries enjoy
• Future mineral-resource shortages will occur and
  cause international tension
• Recycle
• Reduce consumption rate

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Environmental Impacts of Mining

• Air and water pollution
• Occupational hazard
• Underground mining
• Generally hard to see where they are located
• Old, abandoned, and forgotten mines are still a
  problem
• Surface Mining Land Disturbance
• Open-Pit
• Strip
• Spoil banks - pollution

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Impacts Mineral Processing

• Ore rock is ground or crushed for extraction
• The fine waste material is placed in tailings
• The tailings are exposed to wind and weather
• Acid mine drainage
• Harmful elements such as mercury, arsenic,
  cadmium, or uranium can leached out
• The surface and subsurface water systems are too
  often contaminated
• Chemicals used in ore extraction are toxic
• Example cyanide to leach gold
• Smelting ores to extract metals, often produce
  metal laden exhaust gas or ash, sulfur oxide and
  acid rain pollution