 Mineral Resources and Mining
 What is the key vocabulary?
 Mineral - a solid, naturally occurring element or inorganic compound with a crystalline
structure
 Rock - a solid combination of various minerals
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Igneous - formed from molten rock which has cooled and hardened
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Sedimentary - formed from sediment that has accumulated in layers over a period of
years and is cemented together
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Metamorphic - when a previously existing rock through pressure, temperature, or
chemical reaction is changed
 Rock Cycle - the natural recycling of rocks from one type into another
 What are mining resources?
 Non-renewable mineral resources - a concentration of a naturally occurring mineral that can
be extracted for use at a reasonable price
 Ore - rock which can be profitably mined to extract minerals
 An ore is high grade or low grade depending on the amounts of desired materials in the ore.
 Examples: Metallic Minerals - Aluminum, manganese, iron, copper, gold, etc. Non-metallic
minerals: sand, gravel, limestone
 What do we mine for?
 Aluminum
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Most commonly mined element in earth’s crust.
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Bauxite is aluminum ore
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Used in packaging, transportation, and building
 Coal
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Not really a mineral: a rock
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Formed from carbonized plants in swampy areas millions of years ago
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Low S coal from fresh water swamps and high S coal from salt water swamps
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This is the most mined substance in the U.S.

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Wyoming, Kentucky, West Virginia, Pennsylvania
Four types are mined:

Anthracite, lignite, bituminous, and sub-bituminous
 Iron
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Main metal in steel
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Used in tools and machinery
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Silvery, metallic element
 Copper
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Used in electric cables, wires, plumbing, switches, heating, construction, machinery,
alloys, pennies
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Alloys include brass and bronze
 Manganese
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Used in various alloys such as steel because of its corrosion resistant properties
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Also found in batteries and lightbulbs
 How do we find resources?
 Through aerial photos
 Radiation detecting equipment
 Magnetic detecting equipment
 Measuring differences in gravity
 Seismic surveys
 Chemical analysis of water and plants
 Drilling and extracting samples
 What are the mining methods?
 Surface mining – mining just below the surface of earth for shallow deposits of minerals. The
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Overburden - soil and rock
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Spoils - waste material
 What are the types of surface mining?
Open Pit
Holes are dug and minerals removed along with sand, gravel, and stone
Dredging
For underwater deposits
Area Strip Mining
Large amounts of overburden are removed; a shovel digs out deposit; the trench is filled with
overburden and a new, parallel trench is cut; spoil banks are left behind.
Contour Strip Mining
Used on mountain areas; terraces are cut into the hill; a shovel digs out deposits and
overburden is dumped onto terrrace below; highwall is left
Mountain Top Removal
Top of mountain is removed; waste pushed into valleys and streams below; causes significant
environmental damage
 Open Pit Mine
 Dredging
 Contour Strip Mining
 Mining Wastes
 Runoff from Mining
 What is the Surface Mining Control and Reclamation Act?
 Mining companies must return land to the conditions before mining so the land can be used
for the same purposes as before.
 Subsurface mining - for deep mineral deposits which cannot be reached by surface methods.
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A vertical shaft is dug and tunnels are blasted out.
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Disturbs less land and produces less waste.
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Leaves more of the mineral in the ground and is more hazardous to miners as well as
more expensive.
 Images of Subsurface Mining
 Black Lung Disease
 What are environmental effects of mining?
 Scars and disrupts the land’s surface
 Causes subsidence (collapse of ground)
 Wastes are often toxic and can moved by wind or water to other areas
 Acid mine drainage (wastes often contain H2SO4 which can be removed by rainwater)
 Toxic emissions released into air
 Toxic mining wastes stored in pits can harm wildlilfe
 How is metal removed from its ore?
 Ore
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Ore Mineral (portion that contains the desired metal)
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Gangue (waste material in ore)
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Tailings (when gangue is removed, these are the piles of waste remaining)
 Smelting is the process which separates the useful metal from other components of the ore
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Releases air and water pollutants as well as solid hazardous wastes
 Waste
 Mine Subsidence
 Many environmentalists believe that more damage is done by extracting the metals and
creating products than by using up supplies.
 The lower the grade of the ore, the more resources that must be expended to extract it.
 The price of the environmental damage is not passed on to consumers
 How do we determine supplies of minerals?
 Economic depletion occurs when it costs more to utilize the mineral than it is worth.
 When depletion occurs: recycle or reuse materials, waste less, use less, find substitutes, or do
without
 Depletion time - how long before roughly 80% of the mineral reserves are used up at a given
rate of use.
 What are the economics of mining?
 Prices of most minerals are often low due to government subsidies to the mining industry
 Companies are also able to get tax breaks by deducting their costs
 Companies are also able to buy public land at 1872 prices or use public lands without paying
royalties
 What is bioming?
 Use of microorganisms to help extract metal from ore
 Uses natural or genetically engineered bacteria.
 Slow process
 More than 30% of copper produced worldwide is collected by this process
 What is nanotechnology?
 Uses atoms and molecules to build materials
 Creation of buckyballs which could store information, deliver medicines, create appliances
that never need cleaning
 These extremely small particles are potentially more reactive and toxic than larger particles
 How can we utilize the Ocean?
 Remove important chemicals from seawater.
 Mineral deposits along continental shelf
 Deposits found at hydrothermal vents (black smokers)
 Manganese nodules on the ocean floor
 Problems: costs and disagreements over who owns what
 What new materials that could replace current mineral resources?
 Ceramics
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Harder, stronger, lighter, and longer lasting, can withstand high heat and corrosives
 Plastics and composites
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Important to automobile and aerospace industries
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Often much cheaper than traditional materials
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Are light in weight and high in strength