not sure what a blue is myself. the only time I've heard that term is on the early goods referring to umprime goods and not necessarily the coloration of the cat. would love to see a pic of one.
I know around here we get quite a variety in the coloration spectrum. I've seen these reddish colored ones (much like most of our coyotes run) and I've seen some that were more sandy colored like dead winter CRP grasses, etc. Then I've seen some cats that were very dark, charcoal colored nearly top to bottom with few spots. Are those the "blues" you are referring to?
Jim-NE