Black Light Reactions: Gold vs. Diamonds - What to Expect

Question
What color is Gold & Diamond's under a black light?

Answer
Hi, Lynn.  Gold as with most metals does not react to ultraviolet light, the sort produced by a black light.  Mostly, you will see some reflection of the light but no reaction from the gold.

Diamonds are different.  Some fluoresce and some do not.  Fluorescence is the light generated when ultraviolet light strikes certain substances.  You have seen dayglo paint and fabrics in black light and those really light up.  Some diamonds do just the same but some do nothing at all. It all depends on the very basic makeup of a particular diamond.  

Of diamonds which do glow under a black light, most will show a white-like blue color.  A very few will show other color but almost all diamonds which do react to a black light show a bluish glow.

Diamonds which are highly fluorescent, meaning having a strong reaction to UV, will sometimes look sort of oily on the surface when in sunlight, a faint reaction of the diamond to the UV in sunlight.

This should help answer your question.  Oh, in a cluster ring full of diamonds, you should see some which glow and some which do not, scattered in the settings.

God Bless and Peace.  Thomas. July 17, 2008    10:07pm