Hey gang, I'm an author and my next series of books will be mysteries in a wilderness setting. I'm enjoying getting my characters into jams and having them figure a way out. Do any of y'all know if a pair of modern eyeglass lenses (which are mostly polycarbonate) will fracture in a way to make a usable edge? And by usable in this case, I mean to scrape some shavings off dry wood and maybe fuzz up some small sticks. Thanks! If anybody is willing to sacrifice a pair of glasses in the name of an experiment, there's a signed first edition in it for you!