Which Countries Produce the Most Gem Diamonds?
Once centered in Africa, diamond mining now occurs in many countries throughout the world.
Article by: Hobart M. King, Ph.D., RPG
World Gem-Quality Diamond Demand
Diamonds are by far the favorite gemstone of jewelry shoppers in the United States. More than nine out of every ten dollars that they spend on gemstones goes to diamonds. The United States is the largest consumer of gem-quality diamonds in the world, accounting for about 1/3 of all diamond purchases. 
Although the United States is the largest consumer of gem-quality diamonds, it has no commercial mine production. The only location in the United States that currently produces gem-quality diamonds is the Crater of Diamonds State Park in Arkansas, where tourists can pay a small fee to prospect and keep any diamonds that they find. In an exceptional year, the park will produce a few hundred carats. This lack of domestic production requires the United States to import virtually all of its diamond consumption.
Where Are Diamonds Mined?
Since the 1870s, most of the world's gem-quality diamonds have been mined in Africa. The diamond production map above shows countries with at least 50,000 carats of natural gem-quality diamond production. The map illustrates that diamond production has spread to many parts of the world. Diamond production in Russia and Canada has grown rapidly, and these countries diversify the geographic distribution of natural gem-quality diamond production.
Related: How Do Diamonds Form?
Natural Gem Diamond Production Trends
Seven countries have led the world in the production of gem-quality diamonds for over a decade. Russia, Botswana, Canada, Angola, South Africa, the Democratic Republic of the Congo, and Namibia have all been consistently producing over one million carats per year. Their consistent performance and dominance can be seen in the accompanying graph.
Beyond the dominant producers, numerous countries produce less than one million carats per year, but are regular, consistent producers. Australia, Ghana, Guinea, Guyana, Lesotho, Sierra Leone, Togo and Zimbabwe all produce over 100,000 carats of gem-quality diamonds per year and have averaged at least that much for the past decade. This production comes from smaller mechanized mines or an enormous number of artisanal workers in alluvial deposits. Recent production from these countries can be seen in the accompanying table.
Diamonds have been found in Russia as far back as the 18th century. The first significant production occurred in 1957 from the Mir kimberlite pipe and its adjacent placers. Since then, numerous diamondiferous pipes and alluvial deposits have been found. Most of Russia’s diamond production to-date has been from open-pit mines at the Mir and Udachnaya pipes in the Siberian Republic of Sakha.
Today, Russia is the world’s leading producer of gem-quality diamonds on the basis of carat weight and has held that position for over a decade. Botswana is the only country that has a higher production value - mainly because its production includes a high proportion of large, high-quality diamonds.
ALROSA, a Russian group of diamond mining companies, produces almost all of the diamonds mined in the country. ALROSA grades and sells its rough diamonds to a number of polished diamond manufacturers, mostly located in Russia, Belgium, India, Israel, Hong Kong and China. Most sales are through long-term supply agreements, but the company also engages in one-time sales and is developing methods for selling online.
Primary control of ALROSA is in the hands of Russian government agencies. The Russian Federation Agency for Management of State Property owns approximately 44%; the Republic of Sakha’s Ministry of Property and Land Relations owns approximately 25%; and municipal district administrations of the Republic of Sakha own approximately 8%. The remaining approximately 23% is owned by individuals and legal entities.
Botswana was one of the first areas where bulk sampling and indicator mineral mapping were used to characterize and identify diamond pipes across a large and difficult geographic area. Exploration began in the 1950s and diamond mining began in 1971. By the mid-1980s Botswana had some of the highest yielding mines in the world, and the tiny country was among the world's leading diamond producers.
For over a decade, Botswana has been the second-leading producer of diamonds on the basis of carat weight and the leading producer on the basis of value. It holds this position because its average diamond size is larger than what is produced by Russia and of a general higher quality.
Botswana’s Jwaneng mine is often referred to as “the richest diamond mine in the world.” The mine has been producing about 10 million carats of high-quality diamonds per year. The mine is owned by a company named Debswana, a joint venture company between De Beers and the government of Botswana - hence the name “Debswana.”
The diamond industry is the most important contributor to economic activity in Botswana. Diamonds account for about 60% of Botswana’s exports and about 25% of its gross domestic product. De Beers is in charge of selling all of Debswana’s rough and has built the largest diamond sorting and selling facility in the world in Gaborone, the capital and largest city of Botswana. There, stones mined by De Beers in Botswana, Canada, Namibia and South Africa are sorted and offered to diamond buyers and manufacturers from around the world in De Beers’ famous “sightholder sales.”
Related: Diamond Mines in Canada
Canada has been the big surprise in the diamond industry. Geologists suspected that gem-bearing diamond pipes pierced the rocks of the Canadian Shield, but many of the world’s most experienced diamond explorers failed to find them. Then in 1991, two geologists, Chuck Fipke and Stewart Blusson, found evidence of diamond-bearing kimberlite pipes about 200 miles north of Yellowknife, Northwest Territories. The deposit proved to be commercial, and mining there began in 1998. A few other mines came online in rapid succession, quickly making Canada one of the world's leading diamond producers.
Some of Canada’s mines have already been closed as a result of difficult mining conditions or ore bodies being worked out. However, the country’s position as the third-leading producer of diamonds in the world has been maintained. Most of Canada’s mines are in remote and frigid locations in the northern part of the country. Some can only receive their heavy supplies by trucks that travel on ice roads that can only be crossed during the coldest months of the year. The mines must also have all of the facilities needed to house and support their employees for months at a time. The mines have succeeded even when faced with these costly challenges.
Canadian diamonds have been popular with consumers. Some like them because they are being produced away from conflict, where workers are paid well, and where regulations are in place to protect the environment. Diamond and jewelry manufacturers in Canada have promoted their national origin by inscribing their girdles with certificate numbers and trade logos. These include a maple leaf, polar bear, CanadaMark symbols or the words “Ice on Fire.” These inscriptions assure consumers of their diamond’s origin, connects it to a certificate, and has been a very successful marketing feature.
Diamond mining began in Angola over 100 years ago while it was a Portuguese colony. The earliest production was from the country’s many alluvial deposits, and those diamonds were exported to Europe by Portuguese merchants. Today, Angola has been one of the world’s leading diamond producers on the basis of dollar value and volume for over a decade. Alluvial diamond mining remains important, and the discovery and development of several diamond pipes will make hard rock mining an important contributor to Angola’s production.
One mine of particular note is the Lulo Mine, owned by Lucapa Diamond Company. It is an alluvial mine that produces some of the world’s largest type IIa diamonds. Type IIa diamonds are often colorless because they contain very little nitrogen substituting for carbon in the crystal lattice. Some type IIa diamonds from Lulo have an attractive pink color - one of the most popular diamond colors. Large colorless diamonds and attractive pink diamonds give the Lulo production a high value.
South Africa can be considered the birthplace of the modern diamond industry. That occurred in the 1870s when mining began in several diamond pipes near the town of Kimberley. Before then, almost all diamonds were mined from unconsolidated sediments, mostly by artisanal methods. South Africa immediately became the leading producer of gem-quality diamonds and held that position until the 1920s, when production growth in the Democratic Republic of Congo earned that country the title of top diamond-producing nation.
South Africa has remained a consistent producer and now mines a few million carats of gem-quality diamonds per year. Some of this production comes from diamond pipes that were first mined in the 1800s. They began as hand workings in the soil and weathered rock above a diamond pipe, progressed as open-pit mines that excavated deep into the kimberlite, and then went underground when open-pit mining became too costly.
South Africa continues producing diamonds from alluvial deposits and pipes within the country. Diamond mining also takes place along the coastline of the country. For millions of years, erosion removed diamonds from inland locations, and rivers have brought them to the coast and dropped them along with the shoreline sediments. These diamonds are now being mined off the coast of South Africa and even off the coast of Namibia where they have been carried by strong longshore currents and wave action.
Diamond mining started in Namibia in 1908 after a railroad worker found a small diamond in the desert sand. That discovery triggered a diamond rush and extensive alluvial diamond mining activity. The diamonds were distributed through vast amounts of unconsolidated sediment. Innovative miners developed screening and jigging equipment that enabled them to rapidly separate diamonds from enormous amounts of alluvial sediment.
After World War I, a new type of diamond deposit was found - the raised beach deposits along the Atlantic coast. These deposits could also be efficiently mined using the screening and jigging equipment developed for the alluvial deposits. They have been mined continuously since their discovery, and most Namibian diamonds to-date have been produced from these deposits. As these deposits were mined to the coastline, the miners developed methods to mine them from the ocean floor.
Today diamonds are being mined off shore in Namibia’s exclusive economic zone in water over 140 meters deep. This activity has made Namibia the world’s leading undersea miner. The diamonds produced from these deposits are of exceptional quality. They have been weathered from their source rock in the interior of the African continent, washed down rivers, deposited in the Atlantic Ocean and then transported by waves and longshore currents along the African coast. They survive all of this travel in excellent condition because of their hardness and durability. Fractured and heavily included diamonds are more vulnerable to the long-distance transport. As a result, a high percentage of the diamonds produced along the Namibian coast are of gem quality with a very high average value per carat.
Most of the diamond mining activity in Namibia is currently done by Namdeb Diamond Corporation, a partnership owned in equal shares by the Government of the Republic of Namibia and The De Beers Group of Companies.
Australia entered commercial production in 1981 and quickly became the top producer of gem-quality diamonds. In recent years, production in Australia has fallen sharply as deposits there have been depleted with insufficient discoveries to replace them. In 2013, Rio Tinto opened the new Argyle underground diamond mine in Western Australia. The open pit mine at Argyle had been a steady producer of diamonds since 1983 and the world's leading source of natural fancy-colored diamonds. The underground mine should extend Argyle's life until at least 2020.
The Next Big Diamond Discovery?
Where will the next big diamond discovery occur? Perhaps it will be in Canada where another group of difficult-to-find kimberlite pipes are located, or perhaps it will be in the outback of Australia or poorly explored areas of Siberia? Or, could it be in the United States where rocks similar to the Canadian production areas are starting to attract attention?
 Mineral Commodity Summaries 2017: U.S. Geological Survey, January 2017.
 Gemstones: Donald W. Olson, U.S. Geological Survey, 2013 Minerals Yearbook, March 2016.
Diamond Production Is No Longer Confined to Mining!
For many years we published this page when it was very legitimate to use the terms "diamond production" and "diamond mining" as equivalent - at least for gem-quality diamonds.
That has changed.
The United States Geological Survey reports that in 2015, an estimated $52.4 million dollars' worth of gem-quality diamonds were produced in laboratories within the United States. An unknown amount is also being produced in laboratories outside of the United States. Most of these synthetic stones are entering the gemstone market and disclosed as "lab-created" or "synthetic" at the time of sale to consumers. When this occurs these man-made diamonds generally sell at a price that is at least 25% lower than the cost of natural diamonds for stones of similar size and quality.
The man-made diamonds are extremely difficult and costly to distinguish from natural diamonds, especially at the wholesale level when synthetic diamonds are inserted into large lots of very small diamonds. This infiltration of synthetic stones into the stock of natural stones has brought concerns to the gem and jewelry trade and also to consumers. Is my diamond "natural"?
Most consumers are still buying "natural diamonds" because the supply of lab-created diamonds is relatively small. However, a lower selling price attracts certain consumers to lab-created diamonds because they have the same chemical composition, the same physical properties, and to the eye they look exactly like natural diamonds.
Time will tell how dedicated consumers will be to natural diamonds and how much of a discount they are willing to resist.
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