Where Do Diamonds Come From?

Every year approximately 133 million carats of diamonds are bought and sold. 30% of these stones enter the jewellery market where they represent eternity, love and beauty. The remaining 70% of diamonds go to industrial applications. All together these stones provide jobs for about 10 million people around the world.

Rough Diamond Production
Diamonds play an important part in our personal lives and in the world around us, but where do all these diamonds come from?

Diamonds are made from carbon, heat and pressure

Carbon is everywhere. Scientists have found it in the atmosphere and the ocean, in every rock and handful of soil, as well as in our bodies. The majority of this carbon will never become diamonds, because it isn’t exposed to enough heat and pressure.

The only place carbon is transformed into diamonds is in the earth’s mantle which lies 160 kilometers beneath our feet. The mantle is composed of solid rock and is rich in magnesium, iron and carbon. The earth’s core beneath the mantle is made of molten metals. It’s intense heat keeps the mantle at temperatures well above 1,000o C and causes the carbon atoms to form chemical bonds with each other.

Once they have bonded, carbon atoms need to undergo about 50 kilograms of pressure per square centimeter to make them into crystals with rigid, unbreakable bonds. Only a few natural occurrences, including the cataclysmic movement of earth’s tectonic plates and the impact of meteorites, can cause this type of pressure on the earth’s mantle and they happened many years ago.

After carbon has been made into diamonds, the precious stones remain hidden in rock until volcanic activity brings them nearer to the earth’s surface.

Which countries have diamond reserves?

Diamonds have been found in more than 30 different countries located in both the Northern and Southern Hemispheres, but only 10 of these countries stand out for the volume of diamonds that they produce. Here is a list of these countries and the approximate amount of diamonds that they produce every year:

  1. Russia – 38 million carats of diamonds*
  2. Botswana  – 23 million carats of diamonds
  3. Congo  – 16 million carats of diamonds
  4. Australia – 12 million carats of diamonds
  5. Canada – 11 million carats of diamonds
  6. Zimbabwe – 10 million carats of diamonds
  7. Angola – 9 million carats of diamonds
  8. South Africa – 8 million carats of diamonds
  9. Namibia – 2 million carats of diamonds
  10. Sierra Leone – 609 thousand carats of diamonds

*Since the outbreak of war in Ukraine, Russia's production and sales have decreased and it has been unable to export diamonds to countries opposed to the conflict.

Diamond production by country

The list above rates the world’s largest diamond-producing countries by the volume that they produce every year. Now we are going list the same countries and rate them according to value of the diamonds that they produce.

  1. Namibia – US$805.00 per carat
  2. Sierra Leone – US$302.00 per carat
  3. Canada – US$180.00 per carat
  4. Botswana – US$156.00 per carat
  5. South Africa – US$145.00 per carat
  6. Angola – US$136.00 per carat
  7. Russia – US$ 82.00 per carat
  8. Zimbabwe – US$51.00 per carat
  9. Australia – US$32.00 per carat
  10. Congo – US$8.00 per carat

Interestingly, Namibia and Sierra Leone produce the least amount of diamonds every year, but the few that they produce have the highest value in the world. Remember that diamonds with a higher quality and value always enter the jewellery market, while diamonds with lesser value are used in industry.

How did diamond mining begin?

Historians have found evidence of villagers in India finding diamonds in rivers and using them in trade as far back as 400 B.C. India’s diamonds were the only diamonds known in the world until the 1700s when diamonds were found in Brazil.

Brazil Diamond Mining

In the 1700s, Brazil was enjoying a gold rush and as the gold miners panned rivers, they also found a few diamonds.  These South American beauties quickly became popular among the ruling classes and dominated the world diamond market for about 150 years.

By 1867, diamonds were becoming scarce in Brazil. At this same time, a teenager named Erasmus Jacobs found South Africa’s first diamond in a river running through his father’s farm. The Jacobs family continued to find more diamonds near the river on their farm and soon after diamonds were also discovered laying loose in the topsoil of nearby land. Within two years of Erasmus’ discovery, South African diamond hunters who spent their days sifting soil in hopes of finding the precious stones discovered that the layer of rock beneath the soil also had diamonds.

Between 1870 and 1890, a few diamond mining towns were built in Cape Colony, South Africa. The minors who lived in these towns worked long, hard hours breaking and crushing bedrock so that the diamonds in it could be sifted out. Diamond mining had officially begun! 

How does diamond mining actually work?

The first step in diamond mining is for a prospector to find a diamond deposit. Diamond prospectors travel the world testing samples of soil to identify minerals and other rocks which are usually found with diamonds. Prospectors also look for secondary diamond sources that they can trace back to a primary deposit. Once a prospector finds a diamond deposit, mining begins.

Most diamond deposits are found on land, but there are also a few in the ocean floor. No matter where the diamonds are mined from, approximately 250 tonnes of soil, sand and rock must be blasted, crushed and processed to yield a single carat of rough diamond.

Most modern diamond mines are highly mechanized. Controlled explosions break up layers of soil and rock which can be more than 600 meters deep. Tractors and trucks then transport the soil, sand and rock to processing plants where conveyor belts carry it through machines that extract the diamonds.

Modern diamond mine

There are some diamond mines, though, that have not modernized with the times. These mines, which are found primarily in Africa, are worked solely by local villagers. Most of these men and women are born and raised in the diamond mine. They go through their lives using basic equipment to dig up soil, crush rock and sift out diamonds that they sell to support their families.

Blood diamonds and the importance of choosing ethical diamonds

Many African countries, including Sierra Leone, Congo and Angola, have frequent tribal wars and political conflicts. In the 1990s, the tribes and political parties involved in these conflicts began to take control of African diamond mines.

They used the local miners as slaves, forcing them to work and then confiscating the diamonds that they found to finance their wars and political ambitions. Thousands of these enslaved men, women and children worked under inhumane conditions in the diamond mines and were not even given the basic necessities of food, clothes, medical care and education. A great number of these miners gave their lives to find diamonds that were used to finance bloodshed in their own country.

Blood diamond

In July 2000, the World Diamond Congress which was held in Antwerp took a firm stand against the sale of blood diamonds. They passed a resolution to create an international certification system that would regulate the trade of rough diamonds and make it possible to block the trade of blood diamonds. The World Diamond Congress also decided to ban any individual or company found trading blood diamonds and requested all diamond-producing countries to impose criminal charges on anyone involved with blood diamonds.

Following the World Diamond Congress, several diamond-producing states in Kimberley, South Africa worked together to establish the Kimberley Process. The Kimberley Process tracks diamonds from their mine of origin to the diamond market.

Kimberley process certificate

The Kimberley Process distinguishes between blood diamonds and ethical diamonds, which come from mines that invest in their miners safety and well-being, and works to reduce the trade of blood diamonds. Thanks to the Kimberley Process most of the diamonds that are bought and sold today have internationally recognized certificates that they are ethical diamonds. 

What are the largest, ethical diamond mining companies in the world?

The world diamond market is currently supplied by numerous diamond mining companies. These companies vary in the volume and value of the diamonds that they produce, as well as in the type of mines that they operate. Some of them only work with basic pit or alluvial mines, while others also invest in coastal and deep sea mining. Here is a closer look at the top 3 ethical diamond mining companies in the world:

  1. De Beers Group – De Beers currently ranks as the largest diamond mining company in the world and controls about 35% of the raw diamonds on the market. De Beers operates a variety of diamond mines in the ocean floor, as well as in 35 different countries, including Botswana, South Africa and Canada. Along with mining, the De Beer Group is also active in diamond retail and they popularized the slogan “A Diamond is Forever” in 1947
    De Beers Mine
  2. Alrosa – The Russian diamond mining company Alrosa focuses most of their attention on 30 different diamond deposits in Russia, but they are also active in Africa. Alrosa produces about 27% of all the raw diamonds on the market and are known for finding pink diamonds. The largest pink diamond that they have found so far weighs an amazing 25.68 carats.
  3. Rio Tinto – Rio Tinto is a multinational corporation that mines diamonds, as well as metals, such as iron, copper and aluminum.  Rio Tinto operates three diamond mines which are located in Australia, Canada and Zimbabwe and produces 20% of the world’s rough diamonds.

Each of these diamond mining companies are jointly owned by private companies and also countries. For instance: 85% of De Beers is owned by Anglo American plc and the remaining 15% is owned by the government of Botswana. There are other smaller diamond mines, such as Endiama in Angola, which belong solely to countries.

Diamond cutting in the country of origin

For many years, rough diamonds were taken from their country of origin to be cut in diamond centers around the world, including Antwerp, Tel Aviv and New York. Under this system, countries of origin received only a small amount of profit from the diamonds that they mined, because they were exported in their rough state.

In order to increase their profits, many diamond-producing countries now require a certain percentage of their rough diamonds to be cut in the country before they are exported. De Beers, as well as other mining companies, understand the importance of investing in the countries where they mine and willingly supply rough diamonds to local diamond cutting and polishing businesses in order to create job opportunities and encourage economic development within the country.

After being mined, rough diamonds spend several months going through the cutting process, which includes:

  1. Planning how to bring out the beauty in each rough stone
  2. Cleaving to break larger diamond crystals into smaller stones.
  3. Bruting to give the diamond a specific cut that will maximize the light that it reflects.
  4. Polishing to give the gem a silky finish and remove any external blemishes.
  5. Evaluation to establish the gem’s value.
diamond polishing

Once they are cut, diamonds are ready to be sold to jewellery manufacturers and other retailers. At this point, the diamonds are also available to diamond brokers such as Beldiamond. We work closely with our clients to help them find their perfect diamond, as well as to create custom engagement and wedding rings.