The Oppenheimer Diamond, a nearly perfectly-formed 253.7 carat yellow diamond crystal, is one of the largest uncut diamonds in the world. It measures approximately 20 × 20 millimeters. It was discovered in the Dutoitspan Mine, Kimberley, South Africa, in 1964. Harry Winston acquired the stone and presented it to the Smithsonian Institution in memory of the late Sir Ernest Oppenheimer.

Oppenheimer Diamond mining company is a South African diamond mining company founded in 1888 by the Oppenheimer family. The company is one of the world’s leading diamond producers and is the largest diamond mining company in South Africa. The company operates several mines in the country and is responsible for producing a large portion of the country’s diamonds. Oppenheimer Diamond mining company is also involved in the exploration, development and production of diamonds in other countries, such as Botswana, Namibia and Angola. Oppenheimer Diamond mining company is a major contributor to the South African economy, providing thousands of jobs and a significant source of income for many South Africans. The company has a long history of providing quality diamonds to the world market, and its diamonds are renowned for their quality and beauty. The company also has a commitment to social responsibility, and works to ensure that its operations are conducted in an ethical and sustainable manner.

Oppenheimer Diamond mining company has also been a leader in promoting responsible diamond mining practices and has been involved in a number of initiatives to improve the lives of workers and communities in the areas where they operate. The company has also been an active participant in the Kimberley Process, an international diamond certification scheme that seeks to prevent the trade of conflict diamonds.

Oppenheimer Diamond mining company is an important part of the global diamond industry, and its efforts to promote responsible diamond mining practices have helped to ensure that diamonds are sourced and produced in an ethical and sustainable manner. The company’s commitment to social responsibility and its dedication to providing quality diamonds have helped to make it one of the world’s leading diamond producers.