I always saw it as more closely akin to the whole spooky crystal skull scam that was supposed to have come from the Amazon. And yeah, I gotta build a light box for it to sit on.
It all becomes much more dramatic once it's got a proper clear coat on, as it removes the surface haze and makes the splintering effect pop. For these pics I just wetted it down with some mineral spirits so that the details would temporarily show (it's an old wood worker's trick).
As for the quartz effect itself, it's a special technique I developed when I was building the Tri Wizard Cup for Harry Potter. You have to do about 6 seperate pours of clear resin into sheets and then cut them up.
Sounds pretty simple and straight forward, but it's actually quite tricky to pull off correctly. Even the guys that worked with me side by side on the Tri Wizard couldn't duplicate it.