The offspring colors depend on if the rooster carries sex-linked gold or sex-linked silver. The female offspring will be chocolate with non-chocolate (white or buff) on the breast, head and neck hackles- the buff or white may extend onto the back. The males will be black with some blotchy non-black (silver or buff) on the breast, The non-black could be a small amount or the entire breast could be silver or buff. Some chickens carry modifiers that cause the entire breast to be non-black.
what do you mean by quality of color? do you want to produce birds that are solid chocolate? The genetics that produce a chicken of a specific color can be complicated. Most of the time if a chicken does not have a full complement of certain genes, the desired plumage color will be lacking. The greatest percentage of time if you cross two birds that are genetically different, the epistatic plumage color ( chocolate in your case) will not be replete. Some other color; white, red, buff will show up in the plumage.
There will not be any dilution (watered down) of the plumage colors. The male offspring will be black with some white feathers in their plumage, most likely the white will be on the breast and in the neck hackles. The females will be chocolate with some white or red feathers in the hackles. Some non-chocolate color ( red or white) may show on the breast- if it does it will be a small amount.
