I have 6 hens. 2 wyandottes, 2 barred rocks and 2 Australia. They are 6 months old and have been laying for about a month. Today I found a weird egg. It is small and slightly darker with a rough texture at one end. The shell pigment is uneven. The yolk is very large with a proportionally small amount of egg white around it. The membrane within the shell is abnormally thick and strong. Should I be concerned? The picture are from after I broke the shell open. It was a normal shape.