There are six show-acceptable coat colors for Great Danes:
Fawn: Yellow gold with a black mask. Black should appear on the eye rims and eyebrows, and may appear on the ears and tail tip.
Brindle: Fawn and black in a chevron stripe pattern. Often also referred to as a tiger-stripe pattern.
Blue: The color shall be a pure steel blue. White markings at the chest and toes are not desirable.
Black: The color shall be a glossy black. White markings at the chest and toes are not desirable.
Harlequin: Base color shall be pure white with black torn patches irregularly and well distributed over the entire body; a pure white neck is preferred. The black patches should never be large enough to give the appearance of a blanket, nor so small as to give a stippled or dappled effect. Eligible, but less desirable, are a few small gray patches, or a white base with single black hairs showing through, which tend to give a salt and pepper or dirty effect.
Mantle: The color shall be black and white with a solid black blanket extending over the body; black skull with white muzzle; white blaze is optional; whole white collar preferred; a white chest; white on part or whole of forelegs and hind legs; white tipped black tail. A small white marking in the black blanket is acceptable, as is a break in the white collar.