We are new to raising chickens and have got three 14 week old babies mix between rode island reds and Ameraucana.. I can not tell at all by their feathers or cones as people have suggested.. what do I need to post pictures of to help determine?
Those birds all have yellow legs. True Ameraucana have white skin. White skin is dominant. I'm guessing your Ameraucana is a hatchery Easter Egger.
Photos that show the full body of each bird, in natural lighting will help. By 14 weeks, the males should have some visible male feathering on the back, shoulders, or neck.