I need to do a cap study on 300 consecutive pieces to evaluate growth. Normally I would engrave the numbers on them, because most of our heat treated parts get ground. However this one doesn't, and I don't want to have to scrap 300 parts because they are engraved. Our heat treater can segregate the 300, but can't guarantee that we will get them back in sequential order. Does anyone have another method of identifying parts in an instance like this?