I have a hen that lays a normal shape, size, color egg except the top is rough, porous, and very thin. Pic from the phone so not good quality. I am only having this issue with one hen. They are on layena and/or flock raiser and have oyster shell free choice. The also free range quite a bit and get scratch in the evening. The shells are all good and thick. This one is my puzzle. The top is usually cracked from laying fall or being stepped on.