Well, Siamese Sable and Blue Tort are both self-patterned colors, and self is the most recessive in its series, so you can be sure you won't get any agouti or tan-patterned colors. Each of those rabbits is expressing different dominant and recessive genes in other series, so there are a lot of possibilities. The most likely result is Black. Depending on what recessives the rabbits might be carrying but not expressing, you could easily get Blue, Blue or Black Tort, Siamese Sable, Smoke Pearl, Sable Point. Do you have their pedigrees?