Color of male and female

The upper plumage is an even dark brown color overall. Only the ornamental feathers of the male show a moderate sheen. The ornamental feathers of the male, as well as the back and shoulder feathers, are darker in color.

Down: brownish gray.

Serious faults

Uneven in color. Too dark or too light overall. Differently colored feather parts.

Faults

The above serious faults occur to a lesser extend.

Genetic code: https://kippenjungle.nl/Overzicht.htm

Website from Henk Meijers with all available information regarding

chicken genetics including the world famous 

Chicken Color Calculator