The silver dilution is one of the lesser known dilutions, but one that creeps up in a wide range of breeds. The general name is silver or silver dapple, abbreviated as Z, but in Australia it is also known as taffy, and the term chocolate is sometimes used as well.
While it is largely absent in breeds with a lot of arabian or thoroughbred influence, it is the signature colour of the rocky mountain horse. It also appears in pony breeds like the shetland and welsh ponies, draft breeds like the French comtois and Ardennes, gaited breeds like the icelandic, and while it is rare, it is also present in quarter horses and morgans and some warmblood registries.
This dilution only works on black or dark hairs, and overall has a more profound effect on longer hairs like the mane and tail. It is dominant and never skips a generation, but does not show on chestnuts and chestnut-based colours, as those have no black hairs to be affected.
Silver dilutes the mane and tails of black-based horses. It can also have an effect on the black of the lower legs, sometimes diluting it or creating diluted areas. The effect is usually more profound in younger horses as the mane and tail may darken as the horse ages, sometimes to a point where they appear almost undiluted.
In foals silver can be identified by striped hoofs and white eye lashes, though these characteristics may disappear as the horse ages. Both can also be caused by other colours, so presence is no evidence in itself.