On December 1st my Silver Fox Doe had a litter of kits. The majority of them are black as expected, but 3 of them are blue! I'm guessing that the Blue is a recessive gene.....
Yup, dilute is recessive. The blue silver fox used to be showable, but they lost that color a number of years ago because enough blues hadn't been shown at convention during the previous few years. At the moment, black is the only showable color, but there are people working on getting blue and chocolate admitted to the standard. If your rabbits descend from animals from both of those breeding programs, you might even get lilac (dilute of chocolate), but nobody is trying to get that one accepted, as far as I know.