About 2 days ago I butchered 2 roos, and when I opened up the gizzard on one of them I found the usual stones but also some glass which was about the same size as the stones and I could tell it was wearing away as the stones do when they are grinding away at their food. It looked as though it may have been crushed glass such as you would get from a windshield or safety glass, but I know of none on my property. That is not to say there isn't any, and I'm sure a chicken could find it if it existed. Has anyone else ever had this happen? I give them crushed granite but they also free range in the evening about an hour or so.