Oh, I love his markings they are very unique and very dark, they are grey though not black, so maybe one of his parents was a very dark standard, could it be?
Also, I do find that extremes are very rare and hard to find, so maybe that's why some people charge more than other mosaics because it is hard for one chin to come up with markings like that, I even noticed that in the chins.com website they say they get an extreme mosaic, that has half gray and half white, every so many years, don't exactly remember how many, but a couple maybe.
Ying Yang is very cute, and Panda's spot is all black, so she must be an ebony white mosaic then