I recently was mapping a cave and went out looking for crystal textures to create a "hazard". I went to a few of the royalty free sites but could not find a decent crystal texture. Then it occurred to me that I had a box full of crystals that I had picked up at some gem/rock shows, and so I grabbed my digital camera and took some pics. I used them in my encounter map which you can see over in the finished map section.
Here are a few of the better shots. I hope some my fellow cartographers can find some use for them: