More River Stone Archeology

Got another one today. A small spike of some kind, or edge. It is the black one:

 The other item is from Fort McDowell, AZ. It is sort of similar.

On the black one I picked up today, the flakes are quite nice, in a spiral of decreasing size around the tip.

 

In AZ, I always figured these semi-monofacial tools were more than 10K old. Actually I have no idea. But it would be interesting if there was a widespread stone tool tradition that was pre-arrowhead and encompassed AZ and wherever these river rocks came from.