16-7 Supplies of Mineral Resources
What Is the State of Mineral Resources in Canada? Strong but Not Problem-Free
Minerals are widely distributed across Canada. Metallic minerals are concentrated in the Canadian Shield and in the mountains, whereas nonmetallic minerals are commonly found in the lowlands.
Mining has played an important role in Canadian history. The Klondike gold rush of 1897–98 led to the establishment of Dawson and sparked a boom as gold- seekers staked every creek in the Klondike. Today most of Canada’s gold is mined underground or in open pits in Ontario, Quebec, and British Columbia.
Copper was discovered in Quebec in 1859, and the first mine opened in Ascot, Quebec. Copper is often found with other metals such as nickel, zinc, and gold. Today, copper is mined in British Columbia, Ontario, Quebec, and Manitoba. More than 50% of Canada’s copper is used to produce wire.
Iron is mined for the steel industry, usually from open-pit mines in Newfoundland and Labrador, Quebec, and British Columbia. The steel industry is associated with high levels of air pollution because of its reliance on coal for high-temperature heat.
Zinc is often found in conjunction with copper. Most zinc is extracted underground or from open- pit mines in New Brunswick, Quebec, Ontario, and Manitoba. About 50% of zinc is used to galvanize steel and iron to prevent rusting.
Uranium is a radioactive element found in rock; it can be used as fuel for nuclear reactors and as an explosive in nuclear weapons. Canada is the largest producer and exporter of uranium ore. There are currently four active mines in northern Saskatchewan.
Will We Have Enough Nonrenewable Mineral Resources? Making Educated Guesses
The future supply of nonrenewable minerals depends on two factors. One is the actual or potential supply of the mineral and the other is the rate at which we use it.
We never completely run out of any mineral. However, a mineral becomes economically depleted when it costs more to find, extract, transport, and process the remaining deposit than it is worth. At that point, there are five choices: recycle or reuse existing supplies, waste less, use less, find a substitute, or do without.
How Does Economics Affect Supplies of Nonrenewable Minerals? Prices Can Make a Difference If the Market Is Truly Free
Geologic processes determine the quantity and location of a mineral resource in the Earth’s crust. But economics determines what part of the known supply is extracted and used.
According to standard economic theory, in a competitive free market a plentiful mineral resource is cheap when its supply exceeds demand. And when a resource becomes scarce its price rises. This can encourage exploration for new deposits, stimulate development of better mining technology, and make it profitable to mine lower-grade ores. It can also encourage a search for substitutes and promote resource conservation.
Can We Get Enough Minerals by Mining Lower-Grade Ores? Taking It to the Limit
Several factors can limit the mining of lower-grade ores:
One is the increased cost of mining and processing larger volumes of ore.
Another is the avail- ability of fresh water needed to mine and process some minerals—especially in arid and semiarid areas.
A third limiting factor is the environmental impact of the increased land disruption, waste material, and pollution produced during mining and processing.
One way to improve mining technology is to use microorganisms for in-place mining. This biological approach removes desired metals from ores while leaving the surrounding environment undisturbed. It also reduces air pollution associated with the smelting of metal ores and reduces water pollution associated with using hazardous chemicals such as cyanides and mercury to extract gold.