Here is the American Kennel Club standard on the Mantle Great Dane:
Mantle--The color shall be black and white with a solid
extending over the body; black skull with white muzzle; white blaze is optional;
whole white collar is preferred; a white chest; white on part or whole of forelegs
and hind legs; white tipped black tail. A small white marking in the blanket is
acceptable, as is a break in the white collar.
2 examples of mantle 3 week old Great Danes