Gold in a piece of quartz from Manitoba

Gold in a piece of quartz from Manitoba (James St. John [CC BY], Wikimedia Commons)

Mines and Mining

Let's Talk Science

Summary

Learn about mines and mining in Canada and discover how aluminium is mined and refined.

Mines and Mining

Mining is the process of removing minerals from the Earth. A mine is the facility where mining occurs. There are two types of mines. 

Surface mines (A) are used to remove minerals found naturally near the surface of the Earth. In surface mines, minerals (ore) are accessed by digging a big open pit. 

Underground mines (B) are used when minerals are located deep beneath the Earth’s surface. A series of tunnels are used to access the ore.

open pit and underground mines
A: A typical surface mine showing the open pit (Williams Open Pit Mine) (Source: © Lesley Hymers. Used with permission). B: An underground mine illustrating the surface footprint (Kidd Operation-Kidd Mine) (Source: © Glencore Canada Operations. Used with permission).

In both surface and underground mines, rock that contains the ore is blasted into pieces small enough to be loaded onto trucks. The ore is then transported to the mill. A mill is a type of processing plant where the ore is crushed. Valuable minerals are then separated out from the non-valuable rock.

Mine Life Cycle

There are many stages to mining. These stages are referred to as the mine life cycle and include exploration, development, operation and closure/reclamation.

Exploration is the first stage of the cycle. It involves research, field investigations, and analyzing information to find out where the minerals are. Prospectors and scientists go out on the land to search for rocks and minerals. If valuable minerals are discovered and scientific analysis shows that these minerals occur in a large enough quantity, additional work will be completed. Only a small number of these mineral finds will go on to become mines.

A geoscientist looks for minerals in a rock core
A geoscientist looks for minerals in a rock core (Source: ©Northgate Minerals. Used with permission).

Development involves further research and analysis. This includes:

  1. developing a plan for the mine
  2. discussions with government and communities located near the proposed mine to make sure that their needs and requirements are addressed
  3. applying for government permits and licenses
  4. final evaluation of the proposed mine. Depending on the outcomes of this step, the decision can be made to build the mine.

Once the mine has been constructed, it moves into the operation stage. In this stage, rock is excavated (dug) from the ground. The valuable mineral is separated from the surrounding rock and processed. The length of this stage depends on how much mineral ore is present at the mine.

The final stage of the mine life cycle involves closure and reclamation. This includes ending the operation of the mine, removing all buildings and reestablishing the vegetation on the land (reclamation).

Drills are used in underground and surface mines to prepare the rock face for blasting
Drills are used in underground and surface mines to prepare the rock face for blasting (Source: © Triple Boom Jumbo Drill - Sandvik Mining and Construction. Used with permission).

Mining Across Canada

Canada is a large country where many rocks contain valuable minerals. Mining takes place in 12 provinces and territories across the country (everywhere except for Prince Edward Island). Canada is a global leader in mining, producing more than 60 minerals and metals. The map below shows the location of mine types by province and territory. 

Map of Canada illustrating the location of metals mines across the country
Map of Canada illustrating the location of metals mines across the country (©2014 Let’s Talk Science based on an image from Natural Resources Canada).

Base metal (metals such as iron, nickel, lead, zinc and copper) mines are located in many provinces and territories. Precious metals, such as gold and silver, mines are located in British Columbia, Northwest Territories, Saskatchewan, Manitoba, Ontario, Quebec, Nunavut, Yukon, Alberta as well as Newfoundland and Labrador. Uranium, used to generate energy, is mined only in Saskatchewan. Iron ore, used to make steel, is mined in Quebec, Nunavut as well as Newfoundland and Labrador. 

Gold, copper, zinc, nickel, and diamonds are mined in Canada. British Columbia produces the most copper in Canada. Ontario mines produce the most gold and nickel in the country. Manitoba mines produce the most zinc. More diamonds are mined in the Northwest Territories, Ontario and Quebec.

Gold conducts electricity and is used to manufacture electronics and computers. Gold is also used to make jewelry, in dentistry and in medicine. Copper also conducts electricity and heat and is used in power generation and transmission (e.g., copper wiring), automobiles, plumbing and in the manufacturing of cooking utensils like pots and pans. Zinc is mixed with other metals to make brass. It is also used to manufacture musical instruments and housewares and is a key part of automobile components. Zinc can also be added to fertilizers to increase crop yield. Zinc (in the form of zinc oxide) is mixed with other chemicals to make sunscreen. Adding thin layers of zinc to iron or steel, in a process called galvanization, is used to prevent rusting. Diamond is a very hard mineral that is resistant to chemicals. It is used as an abrasive, to make strong drill bits and in jewelry. Canada became a diamond producer in October 1998 when the Ekati Diamond Mine opened about 300 kilometres northeast of Yellowknife. By 2003, Canada was the world's third largest diamond producer on a value basis, after Botswana and Russia.

Ekati Diamond Mine. You can see three open pit mines on the left side
Ekati Diamond Mine. You can see three open pit mines on the left side (Source: Jason Pineau [CC BY-SA] via Wikimedia Commons).

Spotlight on Innovation

Aluminium smelting in Canada

What metal is lightweight, does not rust and can be infinitely recycled? aluminium! aluminium is one of the most widely used metals across all industries. It is used to make everything from pop cans to jet engines.

Aluminium is the most abundant metal in the Earth’s crust. Bauxite ore is a reddish-brown rock found in Africa, South America and Oceania. Bauxite ore, which is also called aluminium ore, is the world’s primary source of aluminium.

Bauxite ore is mined using strip mining. Strip mining is a type of surface mining in which soil and rock are removed in strips. Prior to mining, the topsoil is removed and stored. Bauxite ore is then dug from the ground. Next, the ore is cleaned and crushed. It is then transported to a refinery. At the refinery, the crushed bauxite is transformed into alumina through the Bayer chemical process. The alumina is then shipped to smelters around the world for processing into aluminium. Finally, during reclamation, the stored topsoil is put back into its original place.

One company that is a global leader in aluminium production is Rio Tinto. In Canada, they have one alumina refinery and six smelters. As an organization, they are very concerned about the environment. That is why they use electricity generated by water (hydroelectricity) to run their refinery and smelters. This means that they can produce aluminium with one of the lowest carbon footprints in the world. Also, new technologies are being developed that will eliminate all greenhouse gas emissions from the aluminium smelting process. In Canada alone, if this technology were to be used at every smelter, it could eliminate the equivalent of 6.5 million metric tonnes of greenhouse gases. That’s roughly the same as taking 1.8 million cars off the road.

Another useful product that comes from the aluminium process is anhydrite. This is a by-product of refining alumina. Anhydrite can be used in fertilizer for local growers and farmers. For example, in the Saguenay-Lac-St-Jean region of Quebec, where the Vaudreuil alumina refinery is located, anhydrite is used to fertilize neighboring blueberry crops.

The people at Rio Tinto believe that innovation and sustainable development are key to responsible mining. With new technologies, improved processes and good relationships with local communities, companies such as Rio Tinto can produce important metals, like aluminium, while having the least amount of impact on the environment. 

Aluminium processes
Three-step process to making aluminium (© Rio Tinto. Used with permission).

 

My Career

Adam Brumwell, Autonomous Solutions Manager, Finning Canada

As an autonomous solutions manager I work with mining companies to help them with the specialized equipment needed to automate their operations. This involves training operators and helping companies design the technology-based solutions to make their operations run faster and better than before.

One of the biggest concerns in mining is safety. By automating processes previously done by people, we can increase the safety of workers by taking them out of situations that could cause them harm. It also gives mines better control over processes and the ability to work more effectively. They can remotely monitor their equipment to identify maintenance and repair issues. By closely monitoring their mining operations, our customers can expose their workers to fewer potential hazards which helps to reduce the risk of injury. Reducing potential harm to workers is possible with today’s technology. Instead of sending in workers to address hazards, we can now send a drone onto the customer’s mine site to survey it.

Every day I get to show customers these new autonomous technologies and help them understand what it can do to help keep their workers safe, increase the speed of production and lessen the impact on the environment. I find it extremely rewarding to share my expertise and see the evolution of the mining industry first hand. Our autonomous technologies help identify opportunities in their current operations, as well as assist with planning a project and showing companies how to install, operate and maintain the equipment. It is very satisfying to watch a customer realize the impact of technology, and how they can use it to improve their operations and keep their workers safe. I have a Degree in International Business and Supply Chain Management. I also worked at a mine operation when I finished my education so I have a strong understanding of how mines function. My education and work experience help me to support customers by identifying how these technologies can transform their mining operations.

Adam Brumwell
Adam Brumwell (Source: © Adam Brumwell. Used with permission).

References

The Canadian Minerals and Metals Plan. (n.d.). Mining in Canada.

Natural Resources Canada. (n.d.). Mining & minerals.

Sandlos, J., & Keeling, A. (2009, April 7). Mining. The Canadian Encyclopedia.