Chocolate palomino = chestnut horse + cream gene + sooty
Silver black = black horse + silver gene
Note that the specific gene(s) for sooty haven't been identified yet and so can't be confirmed through testing. All the other genes mentioned have been identified and have genetic tests.
A chocolate palomino CAN appear very similar to a silver black (like the photos Breezy posted) but it's unusual for sooty to express that strongly. You can always tell them apart by genetic testing, and usually based on baby pictures and color of the sire/dam, too.