We have a mixed pen of 12 orpington an a mallard duck. We where pretty sure the mallard laid the green egg as ot is bigger and the shell tougher. We put them in the incubater an ended up with a chick this morning. Im pretty sure its two blackXBuff orpis laying these are they crossed with something else?? Or could they still be orpis. They look a lot like dorkings.