Which Countries Produce the Most Gem Diamonds?
Once centered in Africa, diamond mining now occurs in many countries throughout the world.
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
Leadership positions in the gem-quality diamond production race are constantly changing as new discoveries are made and old mines are worked out. Recent production trends are shown in the accompanying graphs.
Russia began producing diamonds in the late 1950s and became one of the top three producers in 1970. The Russian mines are at high latitude and in demanding environments, yet they continue to produce at high levels. One disadvantage for the Russian mines is that the size of the diamonds is small, usually less than one carat. That significantly lowers their value per carat and makes them a pedestrian material in the gem market.
Botswana holds a place of significance in diamond exploration because it was one of the first areas where intensive and systematic scoop sampling, along with indicator mineral mapping, were used to characterize and identify diamond pipes in a large and difficult geographic area. Much of this work was done in the 1950s and 1960s, 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.
In recent years, Botswana has been the second leading producer of diamonds on the basis of carat weight but the leading producer on the basis of value. It holds this position because its diamonds are much larger than those produced by Russia and of a general higher quality.
Canada is the real surprise. Geologists suspected that gem-bearing diamond pipes pierced the rocks of the Canadian Shield. 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 was proven 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 the mines there are starting to be worked out, and without new discoveries, Canada's position as a leading diamond producer will change. A new mine, Gahcho Kue, is expected to produce its first diamonds in 2016.
Related: Diamond Mines in Canada
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, but the discovery and development of several diamond pipes has made hard rock mining an important contributor to the country’s diamond production. The Catoca Mine is one of the largest diamond mines in the world, and the Lulo Mine has been producing some of the world’s largest Type IIa diamonds. Although diamond mining in Angola has been successful, the success would be greater if many companies were not afraid of making investments there.
South Africa was where the African diamond rush began in the 1870s. It immediately became the leading producer of gem-quality diamonds and held that position until the 1920s, when the Democratic Republic of the Congo entered major production. South Africa has been a consistent producer for the past few decades, with production volumes regularly ranging between 4 million and 6 million carats per year.
Diamond mining started in Namibia in 1908 after a railroad worker found a small diamond. 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 recover tiny 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 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 they are being mined from beneath the seafloor in water over 140 meters deep. This activity has made Namibia the world’s leading undersea miner.
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?
 Gemstones: Donald W. Olson, U.S. Geological Survey, Mineral Commodity Summaries, January 2016.
 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.
Contributor: Hobart King
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