Exam 4: Mining, Minerals, Ores

Resource

volume of rock enriched in one or more useful material

Ore

Body of material from one or more valuable resources that can be extracted economically

Issues mining

Non renewable, concentrated in small areas, easy deposits already found

Types of mining basics

-Metal

-Non-Metals (Building materials, Phosphates, salts)

What is mined more?

94.7% of what is mined is non-metals

Types of mining (Ore deposits)

-Magnetic ore deposits

-hydrothermal ore deposits

-metamorphic ore deposits

-sedimentary and placer ore deposits

Magnetic ore deposits

-Usually metals

- Substances concentrated within a

body of igneous rock

-Substances become concentrated

away from the cooling magma by

various processes

Ex: REE, gold, uranium, titanium,

platinum, iron, copper

Hydrothermal Ore Deposits

-Hot water dissolves valuable material

in an igneous body

- Moves to a cooler area and

precipitates out concentrated valuable

material

- Ex: Copper, zinc, gold, silver, lead,

and many more

Metamorphic Ore Deposits

-Minerals deposits that form as a

result of the metamorphic process

- Two ways to form: metamorphism

of pre-existing mineral deposits or

metamorphism of pre-existing rock

that contain low levels of

mineralization

- Ex: graphite, marble, quartzite,

garnet, mica, talc, corundum

Sedimentary and Placer Ore Deposits

- Substances concentrated

by flowing surface waters

- Form in two ways:

mineral precipitation

from solution in surface

waters or accumulation

of minerals during

sediment deposition

- The velocity of water

determines which

minerals can be carried

- Heavier minerals tend to

be concentrated in areas

with slower velocities

- Ex: gold, gypsum, salt

Ways to mine

Open pit or surface

Deepest underground mine?

AngloGold Ashanti’s

Mponeng Gold Mine, near

Johannesburg, South Africa (2.5 miles below)

Deepest

open-pit mine?

Bingham Canyon Mine

(Kennecott Copper Mine),Southwest of Salt Lake City,

Utah (2.5 miles wide, 0.75 miles

deep)

Surface

-Less Expensive

- Fewer work hazards

- Good for when deposits are

disseminated

- Best for shallow deposits

- Common for building

materials

- Large amount of waste

Underground

-More common in the past

- Used when ore is deep

- Risks for cave-ins and other

hazards

- Requires blasting = dust and

other materials inside of

lungs

- Less waste

Dose mining have the highest fatality rate?

No, Commercial fishing, oil rigs and farming kills more people a year.

Processing

-Removing Ore and Metal from rocks

-Crushing>sieving>separation>chemical processing

-Very water intensive

Bornite

Cu5FeS4 (Copper Iron Sulfide)

Water seperation

Dense materials

Flotation Seperation

Light materials

Froth separator

A chemical binds to desired material and makes it hydrophobic, this make it bind to air bubbles and rise to the top so it can be removed

Magnetic Seperation

Magnetic materials

Chemical processing

Smelting or leaching

Smelting

a process by

which minerals are melted

until bonds are broken,

releasing the desired

element

Ex: smelt bornite because

you only want the copper

Heap Leaching

-Chemical sprayed dissolves mineral until only wanted mineral left.

-When a solution is

allowed to permeate

through crushed ore

- Cyanide used for gold and

silver

- Sulfuric acid used for

uranium and copper

-For lower grade ores

Lithium

-High demand

-used in batteries, nuclear cooling, bombs, alloys

-Magnetic and salt evaporite deposits

Process: water>brine>evaporation

-Atacama Desert Region 50% deposits

Cobalt

-enhance

communications;

headphones, earbuds,

speakers (Ion batteries)

-70% in DRC owned/processed by china

REE

-Hightech

-China controls 95% of world supply

-US gets 90% from China

-Environmental concerns are radioactive tailings and acids from processing/Bad working conditions

-Mountain Pass Mine california only REE in North America

Impacts of Mining

Air pollution, erosion, Acid mine Drainage

-35% of all solid waste is tailings

-Requires large amounts of land for waste disposal

Lead Zinc leak from abondened mining

Picher Oklahoma

abandoned Open pit copper mine

filled with groundwater

creating sulfuric acid

Berkeley Pit; Butte, Montana