Does Your Diamond Change Colors?

There's a sneaky little characteristic that can make a diamond appear to change colors when it's carried from one kind of lighting into another. Let's say you're in a jewelry store and the diamond you love looks nearly colorless. You buy the diamond and take it home to show everyone. When you remove it from the case the diamond looks like it has more of a yellowish tint than it did in the jewelry store. What happened?

The shift might not be your imagination -- the diamond is probably affected by a characteristic called fluorescence, which makes diamonds appear to change color when they are exposed to ultraviolet light (fluorescent and natural). That means your brand new diamond jewelry might look totally different inside under standard incandescent lights than it did under the jewelry store's fluorescent lighting. The change can be a pro or a con, depending on your attitude and the type of color shift that occurs. Here's why.

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