The Color Orange in Chickens

[Birch Run Farm]

I had several hatches of araucanas over the summer season and some of my pullets are blue and orange. Distinctly orange and not a rusty red. I am curious as to how the orange color resulted as none of the parent stock have orange. Can anyone enlighten me?

 

[alicefelldown]

Can you post a picture?

 

[Sonoran Silkies]

They are missing mahogany, so presumably the parents were het.

 

[Birch Run Farm]

I'll work on some photos this weekend. It seems to be an unusual color for chickens.