Please feel free to read this post that has been posted by more than one member here at GoPitbull.com. I think it will help you to better understand the color issue.
All About Your Red-nose, Blue-nose, or Black-nose APBT/Ambull
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ORIGINAL SOURCE: The REAL Pit Bull - Info Center | Advocacy & Rescue | Education | Blog
"Red or blue nose dogs are: a special type of Pit Bull / rare / worth more than black nose dogs": The answer to all of the above is: FALSE!!! Let's talk color in Pit Bulls.
Pit Bulls are traditionally a performance breed. That means that they were originally bred based on how well they performed a certain task, not what they looked like. Color was probably the least important thing that oldtime breeders of Pit Bulls considered. Today, Pit Bulls remain largely a working/performance dog, and so the old way of doing things as far as looks are concerned largely still holds fast. True, many Pit Bulls today are also bred with the show ring in mind, however color is of almost zero importance even in that venue. No one who really knows Pit Bulls is all that impressed by color. A flashy color does not a good dog make, and although many people have favorite colors, breed-saavy people know that it's what's under the coat that counts.
Pit Bulls come in almost every color that is genetically possible in dogs. Some colors are more common (brindle or fawn for instance); some colors you don't see as often (such as spotted or black and tan). One thing is for certain, however: blue and red nosed dogs do NOT fall into the "rare" category--there are many of both colors out there, especially (at least in my area) the red nosed dogs.
There is, unfortunately, a faction of breeders (all unscrupulous), that are attempting to cash in on the current fad of blue and red nosed dogs. These people produce poor quality animals with no thought to health and temperament, their biggest selling point being coat color. Breeders of this type many times charge jacked up prices for their puppies, justfying the high price tag by claiming their dogs are of a "rare" or "special" color. The unsuspecting buyer is duped into believing their animal is extraordinary simply because he happens to have an "odd" colored nose. Breeders of this ilk are especially dubious because not only are they producing bad stock, but they lure their customers in by making false claims.
Do not be fooled by this type!
There are, of course, very ethical breeders that produce blue and red nosed dogs. There are many fine, healthy, stable examples of these color varieties out there. These are dogs bred by people who care about the breed, are knowledgeable about what they are doing, and breed for MUCH more than just a snazzy color. There is nothing wrong with liking one color above another, but one should be an educated consumer. Realize that you aren't just buying a pretty face, but a living, breathing creature that is going to make real demands and require money to care for, time, and patience.
Some people have the mistaken belief that blue or red nosed dogs are a special "type" of Pit Bull. When speaking of such dogs, these sorts are apt to make statements such as, "I have a blue Pit", or "My dog is the red nosed kind". Let's replace "brindle" with "red-nosed": "My dog is the brindle kind." Sort of silly, no? Brindle is just a color a Pit Bull may be, not a "kind" of Pit Bull. Well, ditto red and blue. There is a specific line of Pit Bull known for its red noses; this is the Old Family Red Nose strain. But this was a tight-knit family of dogs bred closely because of their superior ability in the pit. The genetic closeness of the dogs made it easy to pass on certain traits--it just so happens that the traits of the Old Family dogs included not only gameness, but the genes for red noses as well."