On a recent trip to Yellowknife, Northwest Territories, being a tourist, I made a stop into the local diamond museum (and retailer of fine Canadian gems). For those of you who have never visited our country ‘North of 60’, much of the money made in the territories in the last 20 years or so is from diamond mining. Canada is now the third leading diamond producer behind Russia and Botswana and we could move up in that ranking in the next decade with the opening of new mines in Quebec and Ontario. I believed that South Africa and Namibia were still the tops but no longer.

Up until that visit, I viewed diamonds as pretty, sparkly things of which I had my engagement and wedding rings and a pair of earrings so not a huge connoisseur. I would have to say that I have not given diamonds much of a thought at all and knew next to nothing about them. Our tour guide through the museum was quite knowledgeable and mentioned their company name a half dozen times to make sure we remembered so I knew it wasn’t only about sharing information. She glossed over much of the less savoury aspects to this type of mining such as the environmental, social, and cultural impacts and it made me want to know more. When I returned home I thought that I would do a little more research into diamonds, how they are found, how they are mined, what makes them so special, and turn that into a blog post.

So, here we go. This is what I have found out. The diamond is a rare, naturally-occurring mineral composed of carbon and is the hardest known natural substance and the highest level of lustre for a non-metallic mineral known as adamantine. It is so hard in fact that the only thing that can cut a diamond is another diamond. They are mostly known as the crystal clear white gem but they can also come in fancy colours in pink, blue, purple, red, orange, or just about any colour. Colour variations are caused by impurities, heat, or irradiation. The Canadian diamonds tend to range from white to yellow to brown but amazing fancy gems have come from the Argyle mines in Australia. The rarer the colour, the more expensive the price. I looked at a pink quarter-carat diamond from this mine while visiting the museum for the small sum of $3999 (C); I picked up two just as souvenirs. (I bet my friends wish as much.)

Contrary to popular belief and cartoons everywhere, diamonds are not formed from coal. Although both are made up of carbon, carbon is one of the most abundant elements found on Earth; we too are a carbon-based being but also not a diamond. Coal is characterized as amorphous; meaning without a clearly defined shape or form and diamonds are crystalline in structure. Coal is not a pure element either; it is comprised of organic molecules of decomposed plant and animal material which has been compressed for millions of years. Diamonds are formed deep in the Earth’s mantle under very high temperatures and pressures and then transported to the surface via volcanic eruptions in molten magma. Sometimes, in rare cases, diamonds can be formed on the surface of the Earth at the site of sustained meteor strikes. (Diamonds can also be found in meteorites themselves. This is another reason for the possibility of my hunting down meteors.) The last place for production of diamonds is in the subduction zones, which are the areas where one tectonic plate slides beneath another. It should be said that no commercial diamond mines have been developed in deposits of these types.

The main use for diamonds is in industrial arenas used in abrasives; cutting, grinding, drilling, and polishing but they can also be found in coatings in windows, speakers and wear-resistant parts. The worldwide demand for industrial diamonds greatly exceeds the supply obtained through mining so synthetic diamonds are now being manufactured to meet this demand. The sexier use of diamonds is in the gemstone production. Diamonds are arguably the most popular gems and the US is the leading consumer of these gems. In 2014, sales in America alone topped $22.5 billion dollars. (I think I need a diamond mine or two.)

There are two types of diamond mines: open pit (also known as strip mining) and underground and often when the open pit type is exhausted, it can be made into an underground type. The first step is removing all the surface sand and soil to reach the diamond-bearing kimberlite. The removal of entire ecosystems and or lakes is a possibility. One mine in the Northwest Territories has built the most expensive dike around the pit mines to keep out the shallow lake that was above it. If you have never seen a strip mine (or a clear cut logging area for that matter) you cannot imagine how devastating these processes are. There is an open pit mine in Siberia known as the Navel of the Earth that has a depth of 525 metres and diameter of 1.25 km (!). This mine has a no-fly zone over it because helicopters keep getting sucked into the airflow. Now that’s big!

Mining in general is not a friend of the environment and diamond mining has a sad history of blood, destruction, and exploitation but Canadian mines are championed as the more environmental/socially viable option. They are said to consult with and employ indigenous people in the area, close down completely for the caribou rut, and have plans in place to refill the pits after the mines have been exhausted. They are watched a lot closer than their rivals in other countries but most of these mines are far from prying eyes in the North. The diamond itself is a fascinating mineral and it doesn’t look as if our love affair with it is going to end anytime soon. Hopefully, practices will continue to improve in their extraction and production and Canada can lead the way to a more sustainable industry.

–Janice Willson

https://geology.com/minerals/diamond.shtml
https://miningwatch.ca/
https://www.sciencedaily.com/releases/2018/08/180801131610.htm

Photo Source: Staselnik (Wikimedia Commons), The Mirny mine in Siberia, also known as the Navel of the Earth