Diamond
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. At room temperature and pressure, another solid form of carbon known as graphite is the chemically stable form, but diamond almost never converts to it. Diamond has the highest hardness and thermal conductivity of any natural material, properties that are utilized in major industrial applications such as cutting and polishing tools. They are also the reason that diamond anvil cells can subject materials to pressures found deep in the Earth.
Cullinan Diamond
The Cullinan Diamond was the largest gem-quality rough diamond ever found, weighing 3,106.75 carats (621.35 g), discovered at the Premier No. 2 mine in Cullinan, South Africa, on 26 January 1905. It was named after Thomas Cullinan, the mine's chairman. 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 presented it to Edward VII, King of the United Kingdom, who had it cut by Asscher Brothers in Amsterdam.
Golden Jubilee Diamond
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 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.
Cullinan, Gauteng
Cullinan is a small town 30 km (19 mi) east of Pretoria, Gauteng, South Africa. It is a small town along the diamond route that is heavily reliant on tourism and the mine that dominates the skyline. The town is named after diamond magnate Sir Thomas Cullinan.
Excelsior Diamond
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 larger 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 third largest rough diamond of gem quality ever found. It was ultimately cut into ten stones weighing from 13 to 68 carats..
Harry Winston
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.
Letseng diamond mine
The Letšeng diamond mine, found in the landlocked Southern African kingdom of Lesotho, is owned by Gem Diamonds, Ltd. and the government of Lesotho, and at an elevation of 3,100 m (10,000 ft) it is the world's highest diamond mine.
Tiffany Yellow Diamond
The Tiffany Yellow Diamond is one of the largest yellow diamonds ever discovered; its carat weight is 287.42 carats in the rough when discovered in 1878 in the Kimberley mine in South Africa, and was cut into a cushion shape of 128.54 carats with 82 facets—24 more than a traditional round brilliant—to maximize its brilliance. The facet pattern features eight needle-like facets pointing outward from the culet (bottom) facet. Jewelry and diamond historian Herbert Tillander refers to this as a 'stellar brilliant cut', and lists the gem in his book "Diamond Cuts in Historic Jewelry - 1381 to 1910" (1995) among other such diamonds: The Cullinan Diamond, The Koh-I-Noor, the Polar Star, the Wittelsbach, among others.
Diamond (gemstone)
A diamond is one of the best-known and most sought-after gemstones. Diamonds have been used as decorative items since ancient times; some of the earliest references can be traced back to 25,000 - 30,000 B.C.
Petra Diamonds
Petra Diamonds Ltd is a diamond mining group headquartered in Jersey. It has a diversified portfolio, with interests in eight producing mines in South Africa and Tanzania and an exploration programme in Botswana. Petra Diamonds' focus has shifted from exploration to production, becoming one of the largest independent producers of diamonds in Africa. In June 2012, Petra owns 5 of the world's most productive mines historically. These mines include the Cullinan Diamond Mine famed for having produced the world's largest rough and polished diamond. It is listed on the London Stock Exchange.
Kelsey Lake Diamond Mine
Kelsey Lake Diamond Mine is a defunct diamond mine in Colorado, USA. It is located in the State Line Kimberlite District, near the Wyoming border, and consists of nine kimberlite volcanic pipes, of which two were open pit mined.
Lucara Diamond
Lucara Diamond Corp. is a diamond exploration and mining company, operating in southern Africa but established in Canada. In November 2015, Lesedi La Rona, the world's second largest gem-quality diamond ever found, was found at the Karowe mine in Botswana.
Lesedi La Rona
Lesedi La Rona, formerly known in media as Karowe AK6 or as Quad 1 by the personnel at the mine, is the third-largest diamond ever found, and the second-largest of gem quality. Only the non-gem black Sergio and the gem-quality Cullinan were larger. It was found in the Karowe mine, in Botswana on 16 November 2015.