Warning: I almost skipped the 3 inch screen on my screen dig, picking the big one saved the whole sift
Last Saturday I was helping sift dirt at a small dig outside Tucson and had to pick between a 3 inch screen and a 1/2 inch mesh one. I went with the 1/2 inch even though it was slower, because the site lead told me the smaller stuff was where the real clues hide. Took me twice as long to get through my bucket, but I pulled out 4 tiny shell beads and a flake of obsidian that the big screen would have dropped right through. The lead said those beads push the site's date back about 200 years, so I felt pretty good about the slow choice. What screen size do you all run on sandy sites like that?