Here are some pics of bases of first and second antlers to drop. Usually and almost always the first antler off, (unless knocked off while fighting) will have a smooth pedicle area at the base. And an antler pedicle base that has some kind of burr on it is generally the second one to go. The burr is an indication that it was knocked off. Again, nothing is cut in stone, but pretty much on the money for most of the time.
So, if you find a shed antler that has a burr of any kind on it, it's safe to say the other side is on the ground and that he is not still carrying it, although somebody else might be. Also, coyotes will pick them up and carry it off for an untold distance.
