When we got our chicks 4 weeks ago I got what I was told to be 3 Cornish cross 3 barred rock and 2 Americana. One of which I believe is yellow and the other brownish. The problem I'm having is I have 4 yellow chicks that are all growing extremely fast like Cornish cross. I used to be able to tell them apart but not so much these days. My girlfriend pointed out that 3 of them have yellow feet and one of them has feet with a green tint to them. Is that one my Americana? Or did I get 4 Cornish cross?