Hi all. I have 13 hens. 6 are currently laying, the others are just about ready. One of my hens (black star chicken) is all of a sudden laying these eggs (pic attached) with calcium deposits on the shells. I feed 16-18% protein organic layer feed from scratch and peck feeds with Kalmbach Henhouse reserve mixed in. They free range during the day. I clean the coop out every day. Any ideas? Suggestions?