Been playing around a bit to try some things, and this was my result, so I might as well put it up.
The black outlines around the fingers aren't cut/paste sloppiness, but part of the effect... like I said, just trying things out here
This is what I think one could see if (s)he was an experienced crystal user (less experienced will see a less clearer image, unexperienced ones probably none, just hear things and perhaps feel emotions).
Note that this is one of the larger crystals, since there have been crystals known to be embedded in necklaces, weapons and other items for ease of use.
In it of course my favorite subjects, NVranya and Vanaja