I was real freaked out when I cracked open one of my girls eggs and found what I thought was a rock. Once I cut it open I realized it was another egg.
I would try to cut it open and see just what the heck it is. Very odd coming from a commercial farm.
I have heard of someone finding a bread tie in one if their eggs! Weird...especially when you know how things "work" ya know?
Keep us posted!!