1 out of 5 BRs are laying everyday in the next with tiny, but good shell egg. 2 nd chicken layed one hardshell egg on first day but nothing after that. I was heart broken to find two broken eggs on the coop floor today, both with thin shells and stomped on. While cleaning the stuff, I found another dried up thin shell with no yolk. I guessing thats from day before or earlier. My chicken freerange. Should I still provide oyster shells ? Is it possible one chicken is getting enough calcium from freerange but not others ? Or is the thin shell business part of them getting used to the laying process ? Local feed supplier dont have oyster shells, instead he sold me grit (thats like little pebbles) and told me they have enough calcium in them. Is that true ? Sorry for so many questions, but really upset looking at the beautiful eggs broken.