Good article, thanks! We had a large pile of decomposing granite/coarse sand from some trenching we did, and after reading this article I decided to use it in the chicken coop. Seems to be working great so far (well, first 2 days), and now I'm working on a way to sift it. Using it in a brooder and sifting with a screen seems to be a good idea too, so the next time I have chicks I'm going to give it a try.