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Oppenheimer Diamond

opp·​en·​heim·​er di·​a·​mond | ˈəp-en-hī-mər dī-(ə-)mənd

noun

A 253.7 carat yellow diamond, discovered in South Africa in 1964

The Oppenheimer diamond was found in South Africa in 1964 in a mining operation at the Dutoitspan Mine. The diamond remains uncut, and there are few uncut diamonds in the world comparable in size. It measures 20 millimeters across and was acquired by Harry Winston in 1964 when he presented the stone to the Smithsonian Institute, where it remains today. The yellow diamond is 253.7 carats and is considered a nearly perfectly naturally formed diamond, with no additional cutting or shaping having been done to the stone after it was mined. The diamond remains on display in Washington DC today.