Since all Siamese have some form of albinism, it is impossible for them to be black cats. It doesn’t matter if the cat gets the black gene since the Himalayan gene will take over and make the Siamese coat heat-sensitive.
The Himalayan gene is responsible for pointed coats in Siamese cats. Kitten’s extremities are colder than the core, so their points will develop while the hair that is exposed to higher temperatures will stay pale.
A black cat might also be part Siamese if it was mixed with other breeds that don’t possess recessive genes. However, a black cat cannot be Siamese as they need to have colored points to be considered a Siamese breed.
Siamese cat colors that are accepted in the Cat Fanciers Association are Blue, Chocolate, Seal, and Lilac. The four purebred Siamese cat colors are Blue Point, Chocolate Point, Seal Point, and Lilac Point.
If you see advertisements that say a completely black Siamese cat, you should know that it is a scam! However, if you want to buy a Seal Point Siamese, expect to pay around $400 to $1000.