DO NOT ATTEMPT THIS WITHOUT APPROPRIATE LASER SAFETY GLASSES.
OKAY??!!!
Very hard to do this... because the beams are just so intense and the crystal and even the diamonds give off so much refracted light. Strange speckled results in the final pictures from the coherent light.
Marco, been interested in doing this kind of photography for years. ever since I shone one of those cheap market type laser pointers into a cupboard with crystal wine glasses!!