MINING

What Are Minerals?

• A MINERAL is any natural, pure, non-living material found in the rocks of the earth.

• Minerals can be divided into 3 groups– Metallic Minerals– Fossil Fuels– Industrial Minerals

Metallic Minerals

• When metallic minerals are made pure, they become the metals we use everyday.

• Metallic minerals need to have some quality that we value – Beauty (gold, silver)– Strength (iron)– Conducts electricity (copper)– Light and strong (aluminum, tin)

Fossil Fuels

• Fossil fuel is the leftover of biotic material (material that used to be living).

• Coal was one of the first important fossil fuels– When it is under a lot of pressure, coal changes into

diamonds• Oil and natural gas are now the most popular

forms of fossil fuels• Fossil fuel mining requires oil rigs, or other

pumping mechanisms

Industrial Minerals

• Industrial minerals are any mined minerals that are not metallic or fossil

• These are minerals mostly used in industries• Asbestos – protects from fire and heat• Potash – used to make fertilizer• Gypsum – makes drywall• Diamond – not just for jewellery; used as a

cutting tool as well

Where Do We Find the Minerals?

• Saskatchewan – world’s largest potash deposits

• Quebec – major asbestos mines• Northwest Territories – diamonds

Importance of Mining

• Canada is the third largest producer of minerals in the world– United States, Russia are larger

• Largest EXPORTER or minerals – 80% of what we mine we export

• $83 Billion dollars (2001)• Helped to develop road and rail systems– Needed to reach the remote (far away) deposits

How Do We Find Minerals?

• Mineral deposits that are economical to develop are called MINERAL RESERVES

• Metallic minerals are found in IGNEOUS and METAMORPHIC rocks (like on the Canadian Shield)

• In the earth the minerals we want are mixed with other compounds (like rock, other minerals, etc). This mixture is called ORE.

• A MAGNETOMETER generates a magnetic field which ore such as nickel, iron and copper respond to.

• Satellite images and aerial photos give geologists geomorphologic clues.

• Satellites can also be used to create thermal images, infra-red images, and other imaging which various minerals respond to.

• Once a likely spot has been located, geologists will drill CORE SAMPLES

• Using this method, they can locate the edges of the reserve

Mining Methods

• Most mines are located in remote areas• If the ORE BODY is relatively near the surface,

the mining company may choose to STRIP or PIT mine.

• If the ore body is deep inside the earth, UNDERGROUND or SHAFT mining will be used– This method is more difficult, more dangerous and

more expensive

Strip Mining

• Used to mine minerals like coal and oil sands that develop in horizontal layers.

• OVERBURDEN is removed• Ore is shovelled onto trucks or conveyor belts• The ore is removed for processing

Draw a Diagram of a Strip Mine

Pit Mining

• Similar to Strip mining, but used when the ore body extends downward rather than outward

• Overburden is removed• Explosives blast apart the ore• The ore is put onto trucks and trucked out of

the mine for processing

Draw a Diagram of a Pit Mine

Underground/ Shaft Mining

• Used to get at ore deep in the earth• A SHAFT is drilled into the earth at the edge of

the ore body• Horizontal tunnels, called ADITS or DRIFTS are

dug into the body – This is where the ore is removed from– The chamber at the end of the adit is the STOPE

• The rock in the stope is blasted apart with explosives– The debrisis called MUCK

• The muck is transported to an ORE PASS where it falls into a CRUSHER

• As the name implies, the crusher crushes the ore into smaller pieces

• It is funnelled down another ore pass into a SKIP where it is hoisted to the surface and sent for processing

Label the Diagram of a Shaft Mine

How Miners Work

• The MINERS go down the SHAFT in the CAGE• They go into the ORE BODY in an ADIT until

they get to the STOPE• They blast the rock with explosives and the

rubble is MUCK• The MUCK goes down the ORE PASS to the

LOADING POCKET

How Miners Work

• From there it goes to the CRUSHER where it is broken into smaller pieces.

• The crushed ORE is put onto a SKIP and taken to the surface

Processing Minerals

• Metallic mineral ore need to be purified before it is useful

• MILLING separates the mineral from the majority of the waste– Usually a physical procedure

• SMELTING involves heating the remainder until the compounds separate. The metal will generally sink to the bottom of the furnace, where a tap will drain it off

Leftovers

• The waste material produced by mills and smelters is called TAILINGS

• Tailings are often toxic, ugly or otherwise difficult to deal with

• A HUGE issue facing the mining industry today is how to safely get rid of the tailings

• What are some of the other issues the mining industry must face?