South African diamonds have revealed nickel-rich metallic inclusions, offering the first direct evidence of reactions predicted to occur deep in Earth’s mantle. The study shows how oxidized melts ...

The graphite found in your favorite pencil could have instead been the diamond your mother always wears. What made the difference? Researchers are finding out. How molten carbon crystallizes into ...

The discovery of two diamonds originating from the depths of the Earth's mantle reveals a chemical coexistence that ...

A layer of diamonds up to 18 kilometers (11 miles) thick could be tucked below the surface of Mercury, the solar system’s smallest planet and the closest to the sun, according to new research. The ...

Almost 100 million years ago, in what is now Pike County, nature created one of the world's most unusual diamond-bearing formations, the big volcanic "pipe" that now serves as the centerpiece of ...