True Blue Diamonds Can Be Revealed Through Ultraviolet Test

Hope Diamond originally came from French crown. New technique can create huge diamonds Huge African diamond sells for over $12 million.
The Hope Diamond glows a mysterious red when exposed to ultraviolet light, a finding that scientists say can help them "fingerprint" diamonds and tell the real ones from artificial.
The phosphorescence comes from boron in the gem, the same element that makes it appear blue in normal light, explained Jeffrey Port, curator of the National Gem Collection at the Smithsonian's National Museum of Natural History.
The 45.52-carat blue Hope Diamond is on display at the Natural History museum, but Post said lighting conditions there don't allow it to be shown in ultraviolet light. He said the museum hopes to make a video of the stone when it glows — which continues for some time after the light is turned off — so visitors can see that.