Canada had no diamond mines at all until the late 1990s. A discovery near Lac de Gras in the Northwest Territories in 1991 set off one of the largest staking rushes in North American history, and within a decade Canada was a major producer by value. Its mines sit in remote subarctic country, supplied largely by winter ice roads, and Canadian diamonds became known for their documented origin.
The search across the Slave craton
Geologists had long suspected that the old, stable rocks of northern Canada could hold diamonds. The region overlies the Slave craton, a block of ancient crust with a deep, cool root of the kind where diamonds form and survive. Glaciers had scraped across the area during the ice ages, though, smearing indicator minerals across the ground far from their sources and burying many pipes beneath lakes.
Two geologists, Charles Fipke and Stewart Blusson, spent years in the 1980s tracing a trail of indicator minerals such as chrome diopside and pyrope garnet back along old glacial paths. Their search led them to the Lac de Gras area, about 300 km northeast of Yellowknife. In 1991 drilling with the mining company BHP confirmed diamond-bearing kimberlite there. The background on indicator minerals and kimberlite pipes is on the diamond geology page.
The staking rush
News of the find set off a rush in late 1991 and 1992. Companies and prospectors flew in by helicopter and float plane and staked claims over a huge area of the Northwest Territories, and later Nunavut. Hundreds of kimberlites were found in the following years. Most were too small or too poor to mine, but a handful became mines.
Ekati
Ekati, built on the original Fipke and Blusson discovery, became Canada's first diamond mine when it opened in October 1998. It was developed by BHP and later sold to the Dominion Diamond company. Ekati works a group of small kimberlite pipes, many lying beneath lakes that had to be drained before mining. It has used both open pits and underground methods over its life. The name means "fat lake" in the Tlicho language, a reference to white quartz veins that resemble caribou fat.
Diavik
Diavik lies on an island in Lac de Gras, close to Ekati. Its pipes sit under the lake itself, so the operator, a joint venture led by Rio Tinto, built rock-filled dikes in the lake and pumped out the water inside to expose the ground. Production began in 2003. Diavik moved from open pits to underground mining in the 2010s, and its planned life was set to end in the mid-2020s. In 2015 it produced the Diavik Foxfire, a yellow rough diamond of about 187.7 carats, one of the largest found in North America.
Gahcho Kue, Snap Lake and Renard
Several later mines followed the first two:
- Snap Lake, in the Northwest Territories, was De Beers' first mine outside Africa. It opened in 2008 and mined a thin, sloping kimberlite sheet underground. Low returns and high costs led De Beers to stop operations at the end of 2015.
- Gahcho Kue, southeast of Lac de Gras near Kennady Lake, is a joint venture between De Beers and Mountain Province Diamonds. It opened in 2016 and mines several pipes by open pit.
- Renard, in northern Quebec, became the province's first diamond mine when Stornoway Diamond opened it in 2016. It moved underground and faced financial strain in its first years.
Also in the far north, De Beers' Victor mine in the James Bay lowlands of northern Ontario ran from 2008 until about 2019.
Mining in the subarctic
Canada's diamond mines lie far from any town or railway. Most heavy supplies, including fuel, explosives, construction materials and equipment, travel north each winter on the Tibbitt to Contwoyto Winter Road. This ice road runs for several hundred kilometers, most of it over frozen lakes, and is open for only about two months each year. Warmer winters in some years have shortened the season, and operators have had to fly in supplies when the road could not carry everything needed.
Workers fly in and out on rotating shifts and live in camps at the mine. Kimberlite ore is crushed and processed on site with dense media separation and X-ray recovery, described on the page about how diamonds are mined. The mines signed impact and benefit agreements with Indigenous communities in the region, covering jobs, training and business contracts.
Permafrost, cold, wildlife such as caribou herds and fragile tundra ecosystems all shape how the mines work and how they must be closed and reclaimed. Canada's diamond mines also face planned closure dates as their orebodies run out, so reclamation plans and bonds are part of their permits. Siberia's diamond mines deal with similar permafrost and cold; see diamond mines of Russia.
Origin tracking and Canadian brands
Canada's diamonds arrived at the same time as public concern over conflict diamonds from African civil wars. Producers and the Northwest Territories government saw a market for stones with documented origin. Some mines laser-inscribed small polar bear or maple leaf logos and serial numbers on the girdles of polished stones. The territorial government ran a certification program for diamonds cut in the Northwest Territories, and an industry code called the Canadian Diamond Code of Conduct set rules for claiming Canadian origin.
Laser inscription and serial numbers are also covered on the page on diamond certificates and grading reports. A small cutting industry opened in Yellowknife in the late 1990s and 2000s, though most Canadian rough has been cut abroad in centers such as Antwerp and India; see the diamond pipeline for how rough moves to market.
Frequently asked questions
When were diamonds discovered in Canada?
Diamond-bearing kimberlite was confirmed near Lac de Gras in the Northwest Territories in 1991. The first mine, Ekati, opened in 1998.
What are Canada's main diamond mines?
The best known are Ekati, Diavik and Gahcho Kue in the Northwest Territories and Renard in Quebec. Snap Lake and Victor were earlier De Beers mines that have closed.
How do supplies reach Canada's diamond mines?
Most heavy freight moves on a seasonal winter ice road that crosses frozen lakes for a few weeks each year. Workers and lighter supplies travel by air.
Are Canadian diamonds conflict-free?
Canada's mines operate under Canadian law and the Kimberley Process. Some producers add laser inscriptions and origin documents so buyers can trace stones to a Canadian mine.