Apparently, in addition to making stone blades for things like spears and knives, pre-historic humans also used naturally occurring glass and glass-like rocks such as obsidian. The advantage was that the cutting edge was far thinner on glass that had been knapped (chipped off in small pieces by a hammer or other striking tool) than on a stone equivalent. Depending on the materials involved, a stone one probably be more durable overall, but it’s all trade-offs, you know?
In Neal Stephenson’s amazing Snow Crash (one of my top 5 favorite books) one of the various antagonists is a master at crafting and using glass blades.
The modern versions of these knives — made by paleo groups — don’t look all that durable to me. I’d rather have steel. Of course, if glass were really better than steel for knife-making, the worlds knives would be made of glass and I’d be writing a post about the curiosity of the steel knife. But it’s not.
Anyway, these are cool, and I kind of what to try to make one.Buy Lincoln, Fox and the Bad Dog on Amazon.com right now, or get the first half for free right here if you're still on the fence (.epub download to read in iBooks, Google Play Books, etc.)