I recently acquired two young hens (around 6 weeks ago), I was told they had just started laying. Sure enough they continued to lay after they moved to my place for the first 4/5 weeks or so, One lays very blue eggs, the other has always been blue with slightly more of a greenish tinge. However, the eggs that have the greenish tinge have gradually gotten darker over the couple of weeks or so, the last one was a murky brownish green and the chicken that lays the very blue eggs has stopped laying, hasn't laid in a week. So I am trying to work out what might be going on. What could cause the color change? I understand there is a brown coating applied a some point in the laying process, is there something that would cause more brown to be applied? I also have 6 Buff Orpington hens (no roosters), they are laying as normal, all are on the same diet, nothing has changed in their diet. This change seemed to start when I integrated the new hens into the Buff Op's coop. When they first arrived I kept them in a separate coop and run, then moved them to a fenced area where all chickens could see each other but not touch, after a couple more weeks I removed the fence and they have all free ranged together in a garden which is around 3000 sq ft since then. There hasn't been any fighting or aggression, they even eat along side each other without issues. The last step in integrating them was to close up the old coop and I put the new hens on a perch in the night, after that they have gone into the new coop every night on their own when the others do. The one that lays blue eggs only laid a couple of times after moving into the new coop (she used the nest boxes) and then stopped. Any ideas what could be causing these changes? Maybe they are a little stressed with the move, but would that cause a change in egg color? Are there any illnesses that I should be looking out for that might cause this sort of thing?