Rescued a Golden Retriever. She looks purebred ( and is the best dog I've owned in many years!), but the roof of her mouth is black a coal! Does this mean she is a mix or are they supposed to have a black roof?
The roof of her mouth doesn't have anything to do with her breed mix. If you really want to know about the origins of this dog, you can get a blood test from a pet facility such as your local vet. Alot of them supply such technology these days.