The Golden Jubilee diamond gets its name from the King of Thailand, King Bhumibol Adulyadej, who was presented the diamond, previously known as the "Unnamed Brown", by the people of Thailand, to mark the happy occasion of the 50th Anniversary of his Coronation in 1997. Thailand is one of the few countries in the world where the constitutional monarchy is still held in great esteem.
The Golden Jubilee diamond is a fancy yellow-brown diamond, of unknown clarity grade, and having a unique cut, which the cutter of the diamond Gabi Tolkowsky referred to as a "fire rose cushion-cut. The weight of the diamond is 545.67 carats, making it the largest faceted diamond in the world, a rare distinction which was previously held by the 530.20-carat Cullinan I diamond aka the greater "Star of Africa" diamond. The extra-ordinary size of the diamond, confers on it another rare distinction, as the largest faceted brown diamond in the world. Thus the Golden Jubilee diamond holds the twin distinction of being the largest faceted diamond and the largest faceted brown diamond in the world. See table below.
|1||Golden Jubilee||545.67||cushion||fancy yellow brown|
|2||Star of the South||128.48||cushion||fancy light pinkish brown|
|4||Cross of Asia||109.26||radiant||light brown|
|5||Great Chrysanthemum||104.16||pear||fancy brown|
|7||Golden Maharajah||65.57||pear||fancy dark orange brown|
The fancy yellow brown color grade given to this diamond seems to indicate the contribution made by yellow to the overall color of the diamond. This must be in the region of 25 % to 50 %. If it was less than 25 %, the color grade for the diamond would become yellowish-brown, instead of yellow-brown.
As the color intensity of yellow increases, the diamond may fall into the rare Type Ib category, in which the intense yellow color is caused by single nitrogen atoms scattered in the crystal. Nitrogen atoms absorb visible light in the blue region of the spectrum, causing it's complementary color yellow to appear. The brown color of course is caused by the plastic deformation of the crystal, during it's formation deep inside the earth's crust and subsequent rise to the earth's surface, a process that must have taken millions or perhaps billions of years. Thus the Golden Jubilee diamond is in all probability a Type Ib diamond.
The Golden Jubilee diamond was discovered in the year 1985, in the De Beers Premier diamond mines of Transvaal, South Africa, which was also the source of some very famous diamonds, such as the Cullinan, Niarchos, Taylor Burton, Centenary etc. In the rough state the diamond weighed 755 carats, which was the 7th largest gem-quality rough diamond ever discovered in the world. But, after the discovery of the Millennium Star rough diamond in 1990, which weighed 777 carats, the Golden Jubilee rough diamond was pushed down to the 8th place. See table below.
|Country of discovery||Year of discovery||Carat Weight||
|Star of Sierra Leone||Sierra Leone||1972||969.80||3|
|Woyie River||Sierra Leone||1945||770||7|
|Golden Jubilee||South Africa||1985||755||8|
|Kimberley Octahedral||South Africa||616||14|
|De Grisogono||Central Africa||587||17|
|Zale Light of peace||Sierra Leone||1969||435||19|
|De Beers||South Africa||1888||428.50||20|
A comparison of the world's 1st and 2nd largest faceted diamonds the Golden Jubilee and the Cullinan I can be informative and interesting.
1. Both diamonds, the Golden Jubilee and the Cullinan I, have a common origin, having been discovered from the same diamond mine, the Premier diamond mines, in Transvaal, South Africa.
2. The Cullinan was discovered in 1905, but the Golden Jubilee was discovered 80 years later, in 1985.
3. The Cullinan is a D-color, absolutely colorless diamond, but the Golden Jubilee is a fancy yellow brown diamond.
4.The Cullinan I is cut as a pear-shaped diamond, whereas the Golden Jubilee has been cut as a cushion-shaped diamond.
5. The Cullinan was purchased by the Transvaal Government, and presented to the reigning British Monarch King Edward VII, on the occasion of his 66th birthday, which fell on 9th November, 1907. However, the Golden Jubilee, was purchased by the people of Thailand, and presented to the King of Thailand, King Bhumibol Adulyadej, to mark the 50th anniversary of the Kings Coronation.
6. The Cullinan I is part of the British Crown Jewels, mounted on the head of the royal scepter of King Edward VII. Whereas, the Golden Jubilee, is part of the Thai Crown jewels, initially planned to be mounted on the royal scepter or the royal seal, but as yet unmounted.
It is said that the Golden Jubilee diamond, previously known as the unnamed brown, was used by the owners of the diamond De Beers, to test a series of modern tools and equipment developed by the company, for the processing of large diamonds. The person in charge of the cutting was none other than the world renowned diamond cutter, Gabi Tolkowsky, hailing from a family of diamond cutters, with five new diamond cuts to his credit. Under the expert guidance of Gabi Tolkowsky, the tested equipment not only came out with flying colors, passing all the stringent conditions of the test, but the rough diamond also metamorphosed into a beautiful, 545.67-carat, yellow brown, cushion-cut brilliant, surpassing the hitherto largest faceted diamond in the world, the Cullinan I, by 15.47 carats.
The stage was now set for the De Beers Company to give the green light, to the team of cutters headed by Gabi Tolkowsky, to go ahead with the more challenging task of cutting the 599-carat, D-color (top color), Centenary rough diamond, discovered at the Premier mines on July 17th 1986, but unveiled to the world only on March 11th 1988, at a banquet held to celebrate the centenary of the De Beers Consolidated Mines Ltd. Using the same modern equipment, Gabi Tolkowsky's team successfully transformed this rough diamond, into the 273.85-carat, modified heart-shaped, D-color diamond, both internally and externally flawless. The "Centenary Diamond" is said to be the largest, faceted, D-color, flawless diamond in the world.
The faceted unnamed brown diamond was later taken to Thailand, on loan from De Beers, by the Thai Diamond Manufacturers Association, who exhibited the diamond at a Thai Board of Investment Exhibition. It is said that, the unnamed brown diamond was the star attraction at this exhibition, viewed by large crowds throughout the duration of the exhibition, and at one point caused the build up of a one mile long queue of people, eagerly waiting for their turn to view the extremely rare exhibit.
Subsequently, a group of gem and jewelry dealers of Thailand led by Henry Ho, purchased the diamond from De Beers in the year 1995, with the primary aim of presenting it to his Royal Highness, King Bhumibol Adulyadej, whose 50th coronation anniversary was to fall in the year 1997. The diamond was blessed by Pope John Paul II and later by the Supreme Buddhist Patriarch and the Supreme Muslim Imam of Thailand, before it was finally presented to the King, who christened it the Golden Jubilee diamond. The diamond is now part of the Crown Jewels of Thailand.
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Dr Shihaan Larif
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