How do you tell the difference between duck and chicken eggs? I found a white egg in the nestbox today. I assumed it was from my white leghorn, who is around 24 weeks or so. Then I was thinking about it later, and my ducks are supposed to lay white eggs to, and are a few weeks older than her. It's a little bright white egg. I had to wash it and the other eggs off, it's been rainy the last few days and they were covered in mud. Here is the egg between 2 of my wyandotte's eggs.