Some research is best done behind heavy, locked doors. When geologist Jeffrey Post recently embarked on an experiment involving the Hope Diamond, at 45.52 carats, the world’s largest deep-blue diamond ...

Name: Hope Diamond What it is: A 45.52-carat brilliant blue diamond Where it was found: It was long believed that the diamond was extracted from the Kollur Mine in Guntur, India.

On Tuesday, Botswana premiered a blue diamond that could outstrip the storied Hope Diamond: the 20.46-carat, close-to-flawless Okavango Blue.

The Hope Diamond that famously resides at the Smithsonian's National Museum of Natural History in Washington, D.C. has long been known for its inimitable color—a deep, steely blue, shifting ever ...

The Hope Diamond first appeared in the historical record in 1666, when a French gem merchant named Jean-Baptiste Tavernier acquired the then-112-carat gem in India. It's unclear exactly how he got ...

Henry Philip Hope, a London banker and gem collector, owned the stone in the 1830s. The diamond weighs 45.52 carats and is not blindingly white, as we are accustomed to seeing diamonds, but deep blue.

The 45.52-carat diamond has given up one of its secrets to French mineral scientist François Farges and Jeffrey Post, the Smithsonian's curator of minerals.

Botswana has unveiled a blue diamond whose value could outstrip that of the storied Hope Diamond: the 20.46-carat, close-to-flawless Okavango Blue. The diamond was presented in Gaborone, Botswana b… ...

Advanced computer modeling confirms that the world's largest blue diamond boasts an unsavory past. The supposedly cursed gem was cut from an even larger stone stolen during the French Revolution.