A dilute tortoiseshell is a coat pattern rather than a breed. Instead of black and orange, the cat shows blue-gray and cream in patches or a soft marbled blend, a look that comes from a recessive dilution gene. The tortie pattern is tied to the X chromosome, so nearly all of these cats are female.
Most dilute torties you'll meet are domestic shorthairs or longhairs, medium-sized cats of roughly 6 to 14 pounds that often live 12 to 18 years. Shedding is moderate, and longhaired cats need more brushing. Folklore about "tortitude" has little evidence behind it, so what a cat is like depends on its age, history and personality, not its colors. Time spent with a cat tells you far more than the coat.