Skip to main content.

Smithsonian National Museum of Natural History
Website Search Box
Search Item

Boron in blue diamonds

The blue color in the Hope Diamond and others like it is caused by trace amounts of boron. The Hope Diamond was tested to measure its chemical composition and determine the concentration of boron. This study used various spectroscopic methods and time-of-flight secondary ion mass spectroscopy to analyze for boron in natural type IIb blue diamonds, including the Hope Diamond and the Blue Heart Diamond (also a part of the Smithsonian’s National Gem Collection). The study found that, on average, the Hope Diamond contains about 0.6 parts per million boron.

[ TOP ]