Buff black-tail
Color and pattern male
Plumage: rich even buff, except for the black pattern on the tail and wing-flights; a few small black feather-tips are allowed at the lower neck-hackle.
Primary-flights: black with a rich even buff lace, which should be sharp and not too broad.
Secondary-flights: black with a broad, uniformly rich even buff lace on the inner-web; the outer-web is rich even buff, so that when the wing is closed, it is almost entirely a rich even buff.
Tail: main-feathers black, sickles black with rich even buff lacing and light veins; in contrast, most males have such a wide rich even buff lacing on the shorter sickles that they are predominant buff.
Down: light salmon or grey, which should not break through the surface-color.
Note
The male is generally a darker buff than the female.
Serious faults
Buff patches on the tail main-feathers. Absence of black on the wing-flights. Black feather-tips at the lower neck-hackle or distinct shaft-stripes. Uneven, much too light or too dark color. White in any part of the plumage.
Faults
Slightly too much buff on the greater sickles. Insufficient pattern on the wing-flights. Slightly uneven, slightly too light or slightly too dark in color.
Color and pattern female
Plumage: rich even buff, except for the black pattern on the tail and wing-flights; a few small black feather-tips are allowed at the lower neck-hackle.
Wing-flights: similar to those of the male.
Tail: main-feathers black, except the top feathers on each side on either side, which must have a narrow, sharply defined, rich even buff lacing, buff lacing on the other main-feathers is allowed, coverts black with a narrow rich even buff lacing, complete buff is allowed.
Down: light salmon or grey, which should not break through the surface-color.
Serious faults
Buff patches on the tail main-feathers. Absence of black in the wing-flights. Black feather-tips at the lower neck-hackle or distinct shaft-stripes. Uneven, much too light or too dark color. White in any part of the plumage.
Faults
Too broad buff lacing on the tail main-feathers. Insufficient pattern on the wing-flights. Slightly uneven, slightly too light or slightly too dark in color.
Feather details from: http://www.kippenencyclopedie.nl
Website from Johan Albada with more than
5000 photos of chickens, chicken color varieties and feathers.
Genetic code: https://kippenjungle.nl/Overzicht.htm
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Chicken Color Calculator
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