With our headquarters situated in London, DDA Group is involved in every stage of diamond trading.

Our offices in London, Cape Town, Antwerp, Dubai, Hong Kong and Shanghai, oversee every step of the diamond journey. This includes, investment in diamond exploration and mining around the world, diamond buying operations in several countries, rough diamond auctions, cutting and polishing, financing diamond trade, sales of polished diamonds, design, production and sales of our fine jewellery collection, Iris Alexander.

Iris Alexander’s collections feature exquisite, collectable, one of a kind pieces, conceived with sensitivity to the composition and form of a woman. The essence of femininity is conveyed within each design – varying in its interpretation, yet demonstrating the multi-faceted power and personalities of the women who wear them.

Our worldwide investments ensure our presence within every stage of the diamonds journey – from Earth to Elegance. But where does the journey start?

Around 4-6 billion years ago, diamonds were formed 150 – 200km below the earth’s surface in the earth’s mantle and brought to the surface by deep-source volcanic eruptions. These eruptions produced kimberlite and lamproite pipes some of which are known to contain diamonds and are sought after by diamond prospectors. Over millions of years, some of the kimberlite or lamproite pipes that reached the earth’s surface became weathered and eroded from these eruptive deposits. The diamonds contained within the pipes became displaced and were deposited further away from the source and can now be found along ancient river beds, streams or the ocean.

Diamonds were first discovered in India in the 1400s when Indian diamonds were sold in Venice and other European trade centres. Around 300 years later, India’s diamond supplies declined, and Brazil became the world’s major source of diamonds, until 1867 when a huge diamond reserve was discovered in Kimberley, South Africa. The countries that have been the main sources of rough diamonds has changed over time.

Diamonds are formed in an array of sizes, shapes, colours and qualities and it is these different attributes that determine the value of a diamond. These attributes are known in the trade as the four C’s:

  • CUT – this is the shape that the diamond has been cut in to. There are many different shapes with the most popular being a round brilliant. Other shapes include Pear, Oval, Marquise, Princess, Cushion, Radiant, Emerald and Assher.
  • CLARITY – this is the purity of the diamond and whether there are impurities within the diamond. Most diamonds have some impurities and flawless stones are very rare.
  • CARAT – the weight of a diamond is measured in carats. One carat weighs 0.2g and there are 100 ‘’points” that make one carat.
  • COLOUR – the colour of a diamond ranges from no colour (D) to yellow (Z). There are also a variety of fancy colours that are rare and consequently command premium values for their rarity. These can be yellow, pink, blue, red and green to name a few.

Today, diamonds are mined in many parts of the world with more than 30 mines globally producing over $100M per year each. Russia produces the most diamonds from its 16 mines, but a quarter of the world’s production comes from just 4 mines extremely rich mines in Botswana.

The largest diamond ever recovered was in 1905 from the Premier mine in South Africa. The diamond was named The Cullinan diamond (after Thomas Cullinan – the chairman of the mine) and it weighed in at an astonishing 3106 carats. The diamond was given to King Edward and was eventually cut into nine large diamonds and 100 smaller ones. The three largest diamonds formed part of the Crown Jewels and are on display in the Tower of London.

South Africa, as it is responsible for discovering 6 of the largest 20 rough diamonds ever found – more than any other country. If Lesotho is included (as geographically it is within the borders of South Africa) 45% of the largest stones ever found are within these borders.

Other famous diamonds found in South Africa include:

  • The Eureka. Weighing 10.73ct it is one of two diamonds cut from 21.25ct of rough. It is the polished stone from the first diamond found in Kimberley area in 1866.
  • The Excelsior diamond was discovered in 1893 just outside Kimberley on the Jagersfontein mine. Weighing 995.20ct it is currently the 3rd largest gem quality diamond ever to be found.
  • The Centenary diamond is one of the biggest D Flawless rough pieces to be recovered in recent times. In July 1986 at the Premier mine this giant 599ct rough was unearthed and the world’s second largest modern-cut flawless diamond was produced – 273.85ct Pear shape D Flawless.
  • The Jubilee diamond was liberated in 1895 at Jagersfontein Mine just 2 years after the Excelsior was found. The 650.80ct rough piece was polished to produce a 245.35ct polished cushion cut of exceptional colour and quality.
  • The De Beers diamond found in Kimberley was the largest gem stone to be found in the de Beers mines in Kimberley at that time. Weighing 428.50ct in the rough, this yellow octahedron measured 47.6 mm X 38.1 mm making it one of the largest octahedron shapes ever found. It was polished in to a 234.65ct cushion cut and currently resides on display in Israel.
  • The Tiffany diamond was another large gem to be found in the Kimberley mines. Discovered in 1878, this 287.42ct rough piece yielded a stunning 128.54ct fancy yellow polished diamond and is one of the largest fancy yellow diamonds ever discovered
circa 1907:  The Cullinan Diamond, which was subsequently cut in two and presented to Edward VII for mounting in the Royal Sceptre, on show soon after it was discovered.  (Photo by Fox Photos/Getty Images)
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