I've spent a lot of time with archaeological lithics in my life. As an undergraduate, I spent 3.5 years working with and studying lithic debitage. In the collection here, we have about 6000 pieces of chipped stone tools - projectile points and scrapers, mostly. This week I've been photographing some projectile points and processing photos that our intern, Leila, took earlier this month.
I was really struck by the beauty of these tools. They're made from a variety of materials. Around here, you sometimes see projectile points worked from petrified wood. There's quite a bit of petrified wood in the area. There's even a petrified forest nearby (which has a pretty neat museum/interpretive center down the road from it). I think it's just wild how a tree becomes fossilized and then becomes a tool when worked by a skilled craftsperson.