The Premier Mine is an underground

diamond Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure, ...

mine owned by Petra Diamonds in the town of Cullinan, east of

Pretoria Pretoria () is South Africa's administrative capital, serving as the seat of the executive branch of government, and as the host to all foreign embassies to South Africa. Pretoria straddles the Apies River and extends eastward into the footh ...

Gauteng Province Gauteng ( ) is one of the nine provinces of South Africa. The name in Sotho-Tswana languages means 'place of gold'. Situated on the Highveld, Gauteng is the smallest province by land area in South Africa. Although Gauteng accounts for only ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...

. Established in 1902, it was renamed the Cullinan Diamond Mine in November 2003 in celebration of its centenary. The mine is a carrot-shaped

volcanic pipe Volcanic pipes or volcanic conduits are subterranean geological structures formed by the violent, supersonic eruption of deep-origin volcanoes. They are considered to be a type of ''diatreme''. Volcanic pipes are composed of a deep, narrow cone o ...

and has a

surface area The surface area of a solid object is a measure of the total area that the surface of the object occupies. The mathematical definition of surface area in the presence of curved surfaces is considerably more involved than the definition of ar ...

of . The mine rose to prominence in 1905, when the

Cullinan Diamond The Cullinan Diamond is the largest gem-quality rough diamond ever found,Scarratt and Shor, p. 120. weighing (1 lb 5.92 oz), discovered at the Premier No.2 mine in Cullinan, South Africa, on 26 January 1905. It was named after Thomas Cull ...

– the largest rough diamond of gem quality ever found – was discovered there. The mine has produced over 750 stones that are greater than and more than a quarter of all the world's diamonds that are greater than . It is also the only significant source of

blue diamond Blue diamond is a type of diamond which exhibits all of the same inherent properties of the mineral except with the additional element of blue color in the stone. They are colored blue by trace amounts of boron that contaminate the crystalline la ...

s in the world.

Notable discoveries

The

is the largest rough gem-quality diamond ever found, at . It was found by Frederick Wells, surface manager of the Premier Diamond Mining Company in Cullinan, Gauteng, South Africa, on 25 January 1905. The stone was named after Sir Thomas Cullinan, the owner of the diamond mine. There have been various other notable diamonds that have been recovered from Premier Mine. These include: * The Premier Rose – rough * The Niarchos – rough * The De Beers Centenary – rough * Golden Jubilee Diamond – rough * Taylor-Burton Diamond – polished In May 2008, a sparkling shield-shaped diamond (about the size of a ping pong ball) mined from the Premier Mine sold for more than US$6.2 million at

Christie's Christie's is a British auction house founded in 1766 by James Christie (auctioneer), James Christie. Its main premises are on King Street, St James's in London, at Rockefeller Center in New York City and at Alexandra House in Hong Kong. It is ...

Hong Kong Hong Kong ( (US) or (UK); , ), officially the Hong Kong Special Administrative Region of the People's Republic of China ( abbr. Hong Kong SAR or HKSAR), is a city and special administrative region of China on the eastern Pearl River Delta ...

. Cut from a rough, the shield-shaped gem boasts 92 brilliant facets. While internally flawless, the stone has a slight imperfection on the surface that is imperceptible to the human eye, the auction house said. It is the largest colourless diamond to appear on the auction market in the last 18 years, Christie's said. Only three diamonds of more than have appeared at auction. All were sold in

Geneva , neighboring_municipalities= Carouge, Chêne-Bougeries, Cologny, Lancy, Grand-Saconnex, Pregny-Chambésy, Vernier, Veyrier , website = https://www.geneve.ch/ Geneva ( ; french: Genève ) frp, Genèva ; german: link=no, Genf ; it, Ginevra ...

. Naming rights were granted to the new owner. In September 2009, a diamond was found, and is ranked as one of the 20 biggest high quality diamonds ever discovered. Petra Diamonds sold it for $35.3 million on 26 February 2010, breaking a record as the highest price ever paid for a rough diamond. On 18 April 2013 a blue rough diamond was recovered by Petra Diamonds at its Cullinan mine. According to experts it could be worth more than $10m. The find gave a boost to Petra's share price. The mine has produced hundreds of large stones and is famed for its production of blue diamonds. A similar blue rough diamond recovered by Petra in May 2009 was cut into a near perfect stone and fetched just under $10m at Sotheby's. Another deep-blue diamond from Cullinan was auctioned for $10.8m last year and set a world record for the value per carat. On 21 January 2014, Petra Diamonds announced recovery of a blue diamond. According to the current CEO, Johan Dippenaar, it is the "most significant blue diamond" to be recovered by Petra Diamonds. According to Analyst Cailey Barker at broker Numis it "could fetch between $15m and $20m at auction". Decision on what is to be done with the stone will come next week. On 13 June 2014, Petra Diamonds announced that a blue diamond of was found at the Cullinan mine. The diamond, though not yet appraised, is expected to fetch more than 35 million dollars, which was the approximate value of the Heritage Diamond, also found in that mine. Petra Diamonds says that the diamond will not be put up for auction before their fiscal year ends this month.

Purchase by Petra Diamonds

On 22 November 2007,

De Beers De Beers Group is an international corporation that specializes in diamond mining, diamond exploitation, diamond retail, diamond trading and industrial diamond manufacturing sectors. The company is active in open-pit, large-scale alluvial and c ...

, the world's largest diamond producer, announced that it had entered into an agreement to sell the Cullinan mine for R1 billion (US$125 million) to Petra Diamonds Cullinan Consortium (PDCC), a consortium of: * Petra Diamonds 37% stake, with an option to increase to 60% * Al Rajhi Holdings W.L.L. 37% stake * A Black Economic Empowerment foundation 26% stake, comprising a 12% stake held by an employee share trust and a 14% stake held by Thembinkosi Mining Investments (Pty) Ltd On 16 July 2008, Petra announced the completion of the acquisition.

References

External links

* {{authority control Diamond mines in South Africa Underground mines in South Africa Economy of Gauteng Geography of Gauteng City of Tshwane Metropolitan Municipality

Notable discoveries

Purchase by Petra Diamonds

References

Further reading

External links