I finally tried sifting the dirt I dug last summer in my backyard in Tucson and found 11 flakes of chert
I had a pile of dirt sitting behind my shed since last July from when I dug a hole for a fence post, and I ran it through a $25 screen sifter from the hardware store just to see what was in it. Ended up pulling out 11 chert flakes and one broken point that I am pretty sure is Archaic, all from a pile of dirt I almost used to fill in a low spot in my yard. The lesson is that I was basically throwing away flakes every time I dug in that spot and not screening, which I guess is obvious in hindsight. Has anyone else had luck going back through spoils piles they ignored, and what mesh size do you use for a screen?