Purebreds have distinguishing physical features like the Siamese's color points. Unique traits help identify breed.
A cat with ideal breed standards like the Persian's flat face reflects purebred status versus random breeding.
Predictable purebred temperament, like the Ragdoll's relaxed nature, indicates limited outcrossing occurred.
Documentation like pedigrees and breed registries confirm pure ancestry versus unknown parentage of mixed breeds.
Getting a cat from an ethical, selective breeder dedicated to improving the breed suggests purebred status.
Consistent purebred kittens in a litter versus varying appearances indicates outcrossing didn't occur.
Purebreds don't have physical or personality anomalies suggestive of crossbreeding.