Hell, I'd try it. I'm not going to spend the cash on it, but if I found myslef in possession of such an object, after testing on arm hair, and not casueing TOO much bleeding, I'd give it a whirl.

"Josh, honey, what happened to your face...you haven't cut yourself shaving in a while."
"Well, dear, you see, these guys on the internet sent me what is, I guess, a really, really sharp piece of natural glass, and i tried shaving with it."

The eye-rolls THAT would bring about would be record breaking.