I have a couple ameraucana pullets unexpectedly laying pinkish eggs. For two generations, nothing but blue. Now a couple are pinkish and a couple are olive. I've always read that there are two egg shell colors, white and blue. Any variation to that is the result of pigment layered on top of the shell. Much to my surprise, these pinkish egg's shells are not white or blue. They're pinkish. What's up with this? I tore off the inside membrane (except for the small strip you can see, so the shell color on the inside is more easily seen. I also tried scratching the pigment off the outside and it doesn't come off - at least when dry. The inside is lighter colored than the outside, but it's definitely not white.