Bonhams is selling the original manuscript copy, dated 29 January 1908, of the ‘Agreement for the Inspection of the Cullinan Diamond’ between the representatives of King Edward VII and London diamond brokers M.J Levy & Nephews. This document brokered the cutting of the 3,106 carats diamond – still the largest gem-quality rough diamond ever discovered - by the renowned Asscher Company in Amsterdam to create the nine principal Cullinan Diamonds that today form part of the Crown Jewels of Great Britain and the collection of HM Queen Elizabeth II.

 The auction, at Bonhams New Bond Street, includes the original documents, as well as a paste replica of the Cullinan in its original rough crystal form and two replica sets of the nine principal diamonds cut from the uncut diamond. The lot is estimated at £2,000-3,000.

 Emily Barber, Director of Jewellery at Bonhams UK, said: “We are delighted to bring to auction this remarkable lot that is steeped in history and that tells the story of the cutting of the legendary Cullinan Diamond.”

 The rough diamond, so immense that it was initially thought to be a large piece of rock crystal rather than a diamond, was discovered in 1905 near Pretoria, South Africa and named after Thomas Cullinan, chairman of the mine where it was found. 

 The huge gem initially failed to find a buyer and was eventually sold for £150,000 to the South African Transvaal Colony government in 1907 who then presented it to King Edward VII on his 66th birthday in November 1907 as a symbol of South Africa’s loyalty to the Crown.

 Upon receipt of the gem, King Edward VII was advised by his private secretaries, The Right Honorable Baron Knollys and Sir Dighton Probyn, to consult the London diamond brokers Messrs M.J. Levy & Nephews as to how such a diamond could be cut. Arthur and Alexander Levy of the firm brokered the diamond to be cut and polished with the renowned Asscher Company in Amsterdam, who in 1903, just a few years earlier, had undertaken the cutting of the Excelsior Diamond, then the largest known diamond weighing 995.2 carats.

 It was not possible to shape and polish the stone without splitting it, so responsibility fell to the most gifted cleaver of the Asscher Company, Mr Joseph Asscher, to cleave the diamond.

 After a lengthy period of studying the diamond, Joseph Asscher created a 6.5mm deep incision in the diamond over several days, and on February 1908, Mr Asscher’s first attempt to cleave the diamond ended when the blade of his tool broke on impact when he struck the stone.

 After creating stronger tools, he tried again the following week and successfully cleaved the Cullinan into two parts, weighing 1,977 carats and 1,040 carats.

 Over the following months, these diamonds were further polished and cut to create nine main stones, 96 smaller diamonds, and a quantity of polished ‘ends’.

 The nine principal diamonds - named Cullinan I through to Cullinan IX – form part of the collection of Crown Jewels and the collection of HM The Queen. Cullinan I remains the largest polished ‘white’ diamond in the world, weighing 530.20 carats and sits atop the Sovereign’s Sceptre and Cullinan II, weighing 317.40 carats, is set at the front of the Imperial State Crown, in the Tower of London, as ultimate symbols of majesty and kingship.

 The documents and paste replicas, now up for auction in a single lot, were handed down through the business and subsequent owners of M.J. Levy & Nephews and today, after gathering dust for many years in the current owner’s attic, they are offered on the open market for the first time.