An unusual looking Labrador retriever from France has both a gold and black coat.
According to The Retriever, Dog and Wildlife Blog, the unusual looking coat appears to be a somatic black spot mutation that appears in both types of Labradors on occasion.
This is not inherited, but the cells where the black spots are located do not have the e/e mutation that causes the yellow to red coat. Instead, this somatic mutation makes the cells E/e, which gets expressed as black or liver. These dogs are sometimes called mosaics.
http://retrieverman.net/2012/06/25/labrador-pictus/
Another theory for the distinctive coat is a chimera, which happens when two zygotes combine. This dog could be made up of two distinct fertilized eggs– one that would become a black dog and one that would become yellow.
Whatever the cause, it certainly makes for one unusual looking dog!