This is a strange-sounding question, but I am wondering if these crystals pose any threat to herps. I am trying to create a vivarium modeled like a crystal-dotted forest from a video game, but I obviously don't want to put in anything that could hurt an animal. These crystals tend to flake slightly when gripped with a hand, although I don't know if a snake would get any of that on it simply by curving around one.

Two important things to note:
1) The crystals will not have any edges sharp enough that even a snake squeezing around it would be harmed.
2) The crystals will not be placed where any flakes could get into a water source. Neither the water dish nor the drainage layer.

The snake I have in mind to put in it is a Red-Tailed Green Rat Snake, although I'm not married to that idea. I just have these crystals lying around from something else and wanted to make an attractive setup. Obviously, if they pose a threat to animals living around them, I won't put them in.

Thanks for any help.