The one on the left was my second point. I got a few tips from expert knapper Ken Peek working on it with the California Knappers (http://www.primitiveways.com/California_Knappers.html). The two on the right I did alone. These are made from cobbles I collected from a stream near the Middle Fork Davis Creek obsidian mine in Modoc National Forest, CA.
I’ve mounted them on the skeleton of an Opuntia cactus I got off some ancient lava beds in New Mexico.