Jeweler Harry Winston donated the famous Hope Diamond—the largest-known deep blue diamond in the world—to the Smithsonian Institution in 1958. It arrived in a plain brown package by registered mail, ...

Formed millions to billions of years ago, diamonds can shine light into the darkest and oldest parts of the Earth's mantle. The analysis of ancient, superdeep diamonds dug up from mines in Brazil and ...

A pair of diamonds that formed hundreds of kilometers deep in Earth’s malleable mantle both contain specks of materials that form in completely opposing chemical environments—a combination so unusual ...

Pink diamonds are extremely rare and coveted — a now-closed mine in Australia has been the source of 90% of the colored gemstones. Polished pink specimens of the highest grade can sell for tens of ...

Two diamonds from South Africa’s Voorspoed mine provide a rare direct insight into the chemistry of Earth’s mantle. Although diamonds can be formed in multiple ways, the findings add to evidence ...