Tortoiseshell Maine Coons are particolored cats with no white markings. That means no white mittens or white patches.

Those that are largely white with tortoiseshell patches are described as tricolor, tortoiseshell-and-white (in the United Kingdom), or calico (in Canada and the United States).

Tortoiseshell cats have parti-colored coats with patches of various shades of red and black, and sometimes white.

The size of the patches can vary from a fine speckled pattern to large areas of color.

Typically, the more white a cat has, the more solid the patches of color. Dilution genes may modify the coloring, lightening the cat fur to a mix of cream and blue, lilac or fawn; and the markings on tortoiseshell cats are usually asymmetrical.

Photos

Female tortishell cat shown in the photos below;

Male tortoiseshells are rare and usually sterile.

Refrence Links

Wikipedia.org article on Tortoiseshell Cats

Foster, Robert A (2022). "Disorders of sexual development in the cat: Current state of knowledge and diagnostic approach".