Most often this dog is solid black in coloration but may also have a small amount of white coloration on the chest. (caninejournal.com)
With all the dark and black dogs tested, it appears that when there is white coloration anywhere on the dog other than the chest, it is probably a single merle. (abneycatahoulas.com)
This website exists to help explain white coloration in dogs, as clearly as possible. (lethalwhites.com)