Black & White
The black hairs are usually solid black in color and are caused by the Dominant Black gene (K). Only one copy of the gene is required. The black coloring actually masks either the sable or the tanpoint coat. Variations within this coat color include the Seal and Ghost Tri-colors.
Most black English Shepherds have some white on them, even if it is only a small amount. The amount of white can range from minor white markings (usually on the chest and feet) to the Irish White markings (chest, feet and/or legs, tail tip, muzzle, with or without a collar and face blaze). White markings are due to the White Spotting genes. It is possible to have a black English Shepherd with no white at all – solid black.
Black & White/Dominant Black (K)
Depending on what genes the black and white parent is carrying will determine the coat colors of the puppies. Short of having a genetic test run for all the different coat colors, a breeder can usually determine most of the genes carried by breeding the black and white parent to either a black and tan or tri-color mate.
Along with the Dominant Black gene, it is possible for the dog to carry the sable (ayay or ayat) gene, black and tan (atat), recessive clear sable and more.