A gemstone is a piece of mineral crystal which, in cut and polished form, is used to make jewelry or other adornments. However, certain rocks and occasionally organic materials that are not minerals are also used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some soft minerals are used in jewelry because of their luster or other physical properties that have aesthetic value. Rarity and notoriety are other characteristics that lend value to gemstones.
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, and it was cut by Joseph Asscher & Co. in Amsterdam.
Crater of Diamonds State Park is a 911-acre (369 ha) Arkansas state park in Pike County, Arkansas, in the United States. The park features a 37.5-acre plowed field, the world's only diamond-bearing site accessible to the public. Diamonds have continuously been discovered in the field since 1906, including the graded-perfect Strawn-Wagner Diamond, found in 1990, and the Uncle Sam, found in 1924, which at over 40 carats is the largest diamond ever found in the United States.
Gemesis Inc. was a privately held company located in New York City. The company grew synthetic diamonds using proprietary technology.
A diamond cut is a style or design guide used when shaping a diamond for polishing such as the brilliant cut. Cut does not refer to shape, but the symmetry, proportioning and polish of a diamond. The cut of a diamond greatly affects a diamond's brilliance; this means if it is cut poorly, it will be less luminous.
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.
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.
The largest flawless diamond in the world is known as The Paragon, a D-color gem weighing 137.82 carats (27.564 g), and the tenth largest white diamond in the world. The gem was mined in Brazil and attracted attention for being an exceptional white, flawless stone of great size. The Mayfair-based jeweller Graff Diamonds acquired the stone in Antwerp, cut it into an unusual seven-sided kite shield configuration, and set it in a necklace which separates to both necklace and bracelet lengths. Apart from the main stone, this necklace also contains rare pink, blue, and yellow diamonds, making a total mass of 190.27 carats (38.054 g). The necklace has associations with the end of the millennium and was worn by model Naomi Campbell at a diamond gala held by De Beers and Versace at Syon House in 1999.
Gabriel S. "Gabi" Tolkowsky known for cutting the famous Centenary Diamond, is one of the world's most renowned diamond cutters. Known as the father of the modern round brilliant diamond cut. and the great nephew of Marcel Tolkowsky, he is the sixth generation in his family to become well known in the diamond cutting trade.
Diamond is one of the best-known and most sought-after gemstones. They have been used as decorative items since ancient times.
Queen 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.
The Nassak Diamond is a large, 43.38 carats (8.676 g) Golconda Diamond that originated as a larger 89 carat diamond in the 15th century in India. Found in Golconda mines of Kollur and originally cut in India, the diamond was the adornment in the Trimbakeshwar Shiva Temple, near Nashik, in the state of Maharashtra, India from at least 1500 to 1817. The British East India Company captured the diamond through the Third Anglo-Maratha War and sold it to British jewellers Rundell and Bridge in 1818. Rundell and Bridge recut the diamond in 1818, after which it made its way into the handle of the 1st Marquess of Westminster's dress sword.
The Wittelsbach-Graff Diamond is a 31.06-carat (6.212 g) deep-blue diamond with internally flawless clarity, originating in the Kollur Mine, India. Laurence Graff purchased the Wittelsbach Diamond in 2008 for £16.4 million. In 2010, Graff revealed he had had the diamond cut by three diamond cutters to remove flaws. The diamond was now more than 4 carats (800 mg) lighter and was renamed the Wittelsbach-Graff Diamond. There is controversy, as critics claim the recutting has so altered the diamond as to make it unrecognisable, compromising its historical integrity.
Graff is a British multinational jeweller based in London. It was founded by British jeweller Laurence Graff in 1960. A vertically integrated company, Graff operations comprise the design, manufacture and retail distribution of jewellery and watches.
Martin Katz is an American jewelry designer based in Beverly Hills, California.
Cindy Chao is a Taiwanese jewellery designer. She founded her company, Cindy Chao The Art Jewel, in 2004. She is known for her Black Label Masterpiece Collection and Annual Butterfly.
Dharmanandan Diamonds is an Indian diamond manufacturing company headquartered in Mumbai, Maharashtra, India and has manufacturing facility in Surat, Gujarat, India, that manufactures diamonds and jewelry.
Lesedi La Rona, formerly known in media as Karowe AK6 or as Quad 1 by the personnel at the mine, is the fourth-largest diamond ever found, and the third-largest of gem quality. It was found in the Karowe mine, in Botswana on 16 November 2015.
