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The Mining Industry in Canada. A mineral can be defined as a naturally occurring, pure, non-living substance found in rocks. A rock is a combination of minerals in no definite proportions.
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A mineral can be defined as a naturally occurring, pure, non-living substance found in rocks. A rock is a combination of minerals in no definite proportions. • Most minerals are of little or no economic value. The minerals that we think of as valuable today have not always been valued in the past. • For example, uranium was not considered a valuable resource until scientists came to understand the enormous energy that it contained and discovered ways of extracting this energy.
Canada’s valuable minerals can be divided into “3” groups on the basis of their composition: metallic minerals, fossil fuels, and industrial minerals. • Metallic minerals are minerals that, when refined, yield the group of materials that we know as metals. • Some metals are mined because of their rareness and beauty, for example, gold, silver and platinum. Others, like iron, are valued for their strength. • Finally, others have a particular property that can be used to meet a human need. Examples of these include copper, which is well-suited for making electrical wiring, and nickel, which can be mixed with iron to make steel that is resistant to rust.
For the last two hundred years, fossil fuels have provided the great majority of the energy used by modern society. In the 1800s, coal was the important fuel. • More recently, oil and gas have replaced coal for many uses, including transportation and heating.
A list of major industrial minerals and their uses: • Asbestos is used to protect things from fire and heat • Potash is a salt-like mineral used to make fertilizers • Gypsum is a clay-like material used to make sheets of drywall that are used to construct most interior walls in homes, stores, and offices • Diamonds are a very hard mineral used to make cutting tools; it is also used in jewelry • Gravel is a major ingredient in cement, which is used in the construction of most buildings
Industrial minerals vary so widely in their characteristics, it is very difficult to describe them in a simple way. • In fact, it is almost easier to say what they are not – they are all the things that are mined that are neither metallic nor fossil fuels. • Industrial minerals are important. Even common substances like sand and gravel are critical to our lives and Canada’s economy since they are essential in almost any kind of construction.
Many important industrial minerals are associated with particular regions of Canada. • For example, southern Saskatchewan is the world’s most important producer of potash. • Quebec is the most important producer of asbestos • The Northwest Territories is home to Canada’s first diamond mine. • Other industrial minerals, like sand and gravel, are found in most parts of Canada.
Mining is important to Canada in several different ways. • Canada ranks 3rd in the world, behind the U.S. and Russia, in the production of minerals. • We are also the largest exporter of minerals in the world. Canada exports about 80% of what it produces. Canada is able to produce far more minerals than we are able to use.
The total value of all mineral commodities mined in Canada, including metals, nonmetals and coal, increased to a second straight record of $26.4 billion in 2005 compared with $24.3 billion in 2004. • In addition to the $26.4 billion cited above, other components of the Canadian mineral industry – the smelting and refining of domestic and imported ores, concentrates and recyclables (including steel and aluminum) – and oil sands bitumen production bring the 2005 value of mineral industry production to about $60 billion.
The mining industry has also contributed greatly to the development of Canada's transportation system (i.e. railways and roads). • Minerals deposits that are economical to mine are called mineral reserves. • Many mining sites are located in remote areas, far from existing transportation routes. In these cases, the cost and difficulty of developing a mine are greatly increased.
A road has to be built to allow the shipping in of equipment and the shipping out of product. • Mine facilities to extract the ore from the ground and a mill to separate the useful mineral from the ore has to be built. • Housing has to be constructed for the workers. • Fresh water, sewage treatment and electricity must be supplied. • The costs of a mining operation can be staggering. • Mining operations may consist of strip, open pit or underground mining.
STRIP MINING • Strip mining is used to extract minerals, such as coal and oil sands, that are located in horizontal layers near the surface. (1) Overburden (trees, earth, rock) is removed. (2) Blasting may be necessary for some mineral deposits. (3) Material is loaded onto trucks or conveyor belts by shovels or draglines. (4) Material is taken to storage area for shipment to market or processing.
OPEN PIT MINING • Open Pit Mining is used to extract minerals that are located near the surface, but that may extend deep into the earth. • Overburden is removed. • Holes are drilled 10-15m • deep and filled with • explosives. The • rock is blasted apart.
OPEN PIT MINING (3) Ore is loaded into large trucks (which may carry 90 to 250t) by huge shovels. (4) Ore can now be taken to a storage site near the mill.
UNDERGROUND MINING • Underground mining is used to extract mineral ores located deep in the earth. The Process: • Miners take an elevator (cage) from the headframe down to the working area (stope). (2) Holes are drilled in the rock face at the stope and filled with explosives.
(3) The explosive is set off by an electric charge. The rock is blasted apart. (4) After the blast, miners test the walls and ceiling. Rock bolts or timber supports are used to prop up weak areas. (5) Blasted rock is called “muck.” Front-end loaders or small trains remove the muck to a central underground location. The muck is dropped down a large hole (ore pass) to the crusher. (6) The muck is crushed and loaded onto a hoist, called a skip. The skip lifts the ore to the surface. (7) The ore is taken to a storage site near the mill.
PROCESSING METALLIC MINERALS • The ore that is mined is composed mainly of waste rock. Iron ore is usually half waste rock. • The processing of most ores, including nickel, copper, gold, silver, and zinc, has two steps: milling and smelting. • The mill starts the process of purifying the mineral by separating it from waste rock. • The metal, although far from pure, is now in a concentrated form. For example, a concentrate of copper contains 30% copper and 70% waste rock. The next step is to take this concentrate to the smelter.
A smelter is very costly to build. In some cases it could cost as much as $1 billion or more. As a result, a mining company has to decide if a mine will produce enough to justify the smelter at the mine site. A company may choose to transport the concentrate to an existing smelter offsite. • At the smelter, the ore concentrate and a substance called flux are melted together in a furnace. The flux joins with the waste rock to form a material called slag. The slag is lighter than the liquid metal and rises to the top. The almost pure metal is then poured into molds.
THE PROCESSING OF METALLIC MINERALS • Waste materials, called tailings, are produced during the processing of metal ores. • Tailings, which are a mixture of water, the chemicals used in the process, and rock particles, are poisonous and must be carefully handled.
THE PROCESSING OF METALLIC MINERALS • They are dumped into tailing ponds that are contained within dikes (earth walls to hold back a liquid). • These dikes are designed to prevent the mine waste from seeping into nearby lakes and rivers. The water in the tailings eventually evaporates, leaving solid waste behind. • This is then treated with fertilizers and other chemicals to allow trees and grasses to grow.
How can the development of Canada’s mineral resources be improved in the future? Here are some things to consider: • Environmental controls on mining should continue to improve • Restrictions on mining companies in Canada should still allow these companies to compete internationally • Canadian companies should adjust to international competition and pricing
Canadian governments should continue to provide substantial financial assistance to the mining industry • Canadian mining companies should develop new technologies that will make their operations more efficient • Companies should continue to explore for new deposits in all area of Canada including undersea locations • More of the processing and manufacturing of Canadian minerals should take place in this country
Research and development of new uses for minerals should be intensified • We should try and adjust to the boom and bust nature of a mining-based economy more efficiently.
Short Response Questions Answer all questions in complete sentences. Don’t forget your textbook! Use examples throughout.
Describe the steps used by mining companies to discover and develop an ore body. • Compare milling and smelting in terms of what each does and where each might occur. • Describe the cycle of a boom-and-bust economy in a mining community.
Read the following statement. Be sure to consider both sides of the issue, and then indicate with which side you agree and why. “Cleaning up the tailings area of a mine which has shut down is very expensive and really not necessary since such areas cover only a tiny percentage of the countryside.”
