Here's a good example of why you can't judge a book by its cover. When I first came across this image on Ffffound I thought "Wow. That's a cool Styrofoam skull." Then I did a little digging, discovered that it's by an artist named Fabio Viale, and he works exclusively in marble. That's right. The skull you see here was carved out of a solid piece of white MARBLE!! You should check out the guy's site. He's incredibly talented. He's managed to carve marble so it looks like everything from rolls of toilet paper, paper airplanes, paper bags and balloons. He even carved himself a marble boat that actually floats!