Excellent contrast (and a perfect white background). The dark spots on the rock hurt this a bit. Perhaps with a different approach, if possible: a dark background and light shining through the crystal--making it sort of glow--you may have made your prediction! Hmm, now that I think about it, isn't that the cover of Pink Floyd's "The dark side of the moon"? I'd love to see you post any other attempts.
BTW -- thanks for giving your special sense of humor to DPC!
I wouldn't have cropped off the top of the object. I think the composition would have been stronger on this if this was fliped so that my eye was being drawn into the right hand part of the photo, instead of to the left.
with this kind of minimal photography, you need to either get the whole object into your frame, or make a clear choice to cut off a part. not cut off such a tiny little corner.
otherwise excellent photo, OK for the challenge.