Radio or any other wave in electromagnetic spectrum?
And at what frequency(ies)
Well, at an oblique enough angle, they'll certainly reflect EM waves between 440nm and 770nm. Of that we can be sure.
Visible light is part of the EM spectrum, and a diamond's particular talent at refracting that is why they're sold as horrendously expensive jewelry. (Optical reflection is just a special form of refraction.)
And just about everything solid reflects sound, in one way or another.
The can reflect some waves sometimes, but they can't reflect all the waves all the times.
At the Bragg angle they reflect x-rays.
Pretty much anything with index of refraction not equal to 1 will reflect some EM radiation at its surface (assuming it is surrounded by air or vacuum) in accordance with Fresnel reflection http://en.wikipedia.org/wiki/Fresnel_equations
Metals are a weird case because they have complex refractive indices, but diamond simply follows the equation.
Sound is not an EM wave but diamond will reflect it as well. Actually it will reflect is very well if the diamond is in air, as the impedance mismatch is huge.
Thanks for replies fellas.
Can you "charge" diamonds (rough) with lets say, electromagnetism?
There's a lot more to the article, but this is as far as I dare quote due to copyright.
What do you mean by "charge"? Charge with what?
Like, get a cat and rub the diamond on the cat and notice the static electricity?
"If you like it then you should have put a ring on it."
Oh, if that's all you want to do, you can go a lot cheaper; just use amber. Or, for the wealthier class, even gold or platinum. Diamond won't work.
I would like to be able to afford a big enough diamond to have any significant reflections out in the open! :)
A lady / fiancee with particularly big hands needed too.
Diamond is like all solids, being much more dense than air - and a pretty stiff material, too.
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