Diamond cutting is the practice of shaping a diamond from a rough stone into a faceted gem. Cutting diamonds requires specialized knowledge, tools, equipment, and techniques because of its extreme difficulty.
The Cullinan Diamond is the largest gem-quality rough diamond ever found, weighing 3,106 carats (621.20 g), discovered at the Premier No.2 mine in Cullinan, South Africa, on 26 January 1905. It was named after Thomas Cullinan, the owner of the mine. In April 1905, it was put on sale in London, but despite considerable interest, it was still unsold after two years. In 1907, the Transvaal Colony government bought the Cullinan and Prime Minister Louis Botha presented it to Edward VII, the British king who reigned over the territory. It was then cut by Joseph Asscher & Co. in Amsterdam.
The Golden Jubilee Diamond, a 545.67 carat brown diamond, is the largest cut and faceted diamond in the world. It outweighs the Cullinan I by 15.37 carats. The Golden Jubilee Diamond was discovered in 1985 at the Premier Mine, which is also the origin of the Cullinan diamond (1905) and other notables such as the Taylor–Burton (1966) and the Centenary (1986). Cullinan I, also known as the Great Star of Africa, had held the title of the largest cut and faceted diamond since 1908.
A diamond cut is a style or design guide used when shaping a diamond for polishing such as the brilliant cut. Cut refers to shape, and also the symmetry, proportioning and polish of a diamond. The cut of a diamond greatly affects a diamond's brilliance—a poorly-cut diamond is less luminous.
The Excelsior Diamond is a gem-quality diamond, and was the largest known diamond in the world from the time of its discovery in 1893 until 1905, when the Cullinan Diamond was found. It was found on June 30, 1893, at the Jagersfontein Mine in South Africa, 130 kilometres south east of Kimberley whose fame as a diamond mining center always overshadowed that of Jagersfontein. It had a blue-white tint and weighed 971 old carats or 995.2 metric carats. The Excelsior rates as the fourth largest rough diamond of gem quality ever found. It was ultimately cut into ten stones weighing from 13 to 68 carats.
The Jubilee Diamond, originally known as the Reitz Diamond is a colourless, cushion-shaped diamond weighing 245.35 carats, making it the sixth largest diamond in the world. It was originally named after Francis William Reitz, the then president of the Orange Free State where the stone was discovered, before being renamed to honour the 60th anniversary of the coronation of Queen Victoria in 1897.
Harry Winston was an American jeweler. He donated the Hope Diamond to the Smithsonian Institution in 1958 after owning it for a decade. He also traded the Portuguese Diamond to the Smithsonian in 1963 in exchange for 3,800 carats of small diamonds.
Diamonds were largely inaccessible to investors until the recent advent of regulated commodities, due to a lack of price discovery and transparency. The characteristics of individual diamonds, especially the carat weight, color and clarity, have significant impact on values, but transactions were always private. With the standardized commodity as an underlying asset, several market traded financial instruments have been announced.
A gemstone desired to be used in jewelry is cut depending on the size and shape of the rough stone, as well as the desired piece of jewelry to be made. As a general rule, a cut gemstone will reduce the mass by about 50%.
A trilliant cut, sometimes called a trillion, trillian, or Trielle is a triangular type of gemstone cut. The cut has many variations. It may have curved or uncurved sides. The shape of the top surface, or table, also varies. Stones typically have 31-50 facets.
Lodewyk van Bercken was a mid- to late-15th century Flemish jeweller and diamond cutter, renowned in the industry for inventing the scaif. The device revolutionized the diamond cutting industry and contributed to increased popularity of diamonds.
Gabriel S. Tolkowsky was a Belgian-Israeli diamond cutter, best known for cutting the Centenary Diamond. He was the great nephew of Marcel Tolkowsky, father of the modern round brilliant diamond cut. He is the sixth generation in his family to become well-known in the diamond cutting trade.
Diamond is a gemstone formed by cutting a raw diamond. Diamonds have high monetary value as one of the best-known and most sought-after gems, and they have been used as decorative items since ancient times.
Royal Coster Diamonds is a diamond polishing factory in Amsterdam, Netherlands. Founded in 1840, it is the oldest in the world, and has handled a number of historical masterpieces. For example, it re-polished the Koh-i-Noor, which is mounted in the British Crown of Queen Elizabeth The Queen Mother and the Dresden Green Diamond, held in the New Green Vault at Dresden Castle.
Elizabeth II owned a historic collection of jewels – some as monarch and others as a private individual. They are separate from the gems and jewels of the Royal Collection, and from the coronation and state regalia that make up the Crown Jewels.
Abraham Asscher was a Dutch Jewish businessman from Amsterdam, a politician, and a leader of his community who attained notoriety for his role during the German occupation of the Netherlands (1940–1945).
The Woyie River diamond was recovered on 6 January 1945 from the Woyie River near Koidu in eastern Sierra Leone. The uncut stone weighed 770 carats (154 g), and at that time it was the largest alluvial diamond ever found, and the third largest diamond discovered in Africa, after the Cullinan Diamond and the Excelsior Diamond. The alluvial Star of Sierra Leone, discovered at the Diminco mine in Sierra Leone in 1970, is larger at 968.9 carats (193.78 g) uncut.
The Kazanjian Red Diamond, previously known as the Red Diamond, is a 5.05-carat red diamond. It was found in South Africa in the 1920s, and was cut in Amsterdam. The Nazis seized the diamond during World War II. It was rediscovered after the war, and changed owners multiple times before it was bought in 2007 by the Kazanjian Brothers.
Crown Jewels of the Netherlands is the jewellery used by the Dutch royal family, which is sometimes dubbed "crown jewels". In the past, the terms "House-diamonds", "House-jewels" and "family jewels" have been used. In 1790 the term "Bijoux de la Couronne" was used by Luise of Brunswick -Wolfenbüttel to refer to a large diamond from Borneo. In 1896 the Firm of van Kempen & Begeer wrote about resetting the jewels of the Crown. Queen Juliana gave a selection of her formal jewelry to the new Foundation Regalia of the House of Orange-Nassau, instituted on 27 July 1963. In 1968 a Foundation "Kroongoederen van het Huis van Oranje-Nassau" was instituted. It owns the regalia and the House-jewels.
The Marie Louise Diadem is a diamond and turquoise diadem on permanent display at the National Museum of Natural History in Washington D.C.. It is named for Marie Louise of Austria, the wife of Emperor Napoleon of France.
