Never ever heard of such - I know there are Blue Wheatens and straight Blues (we're in the middle of hatching 15!
) as well as Blue Coppers, but otherwise, no. . . Sounds slightly interesting, but I'm curious as to the quality of them. Most cuckoos are hatchery quality, and often it takes a truly experienced person to properly cross Marans colors and keep the quality in the egg.
Found someone, seems to match your details. The mix in selling is because of the genetics of the blue (Andalusian based) and the barring - The barring splits, and you can't just get straight blue from blue or blue/black parents. Also, chick prices like that you'd need to question. Either they're actually a reputable breeder or trying to rip someone off with an unfinished project bird. I wouldn't pay that money per chick for Marans unless Bev Davis herself sold them to me, and they were that good.
Yep All you gotta do to get all blue cuckoo is cross a Cuckoo Marans rooster on Splash Marans hens, If you use a blue roo instead of a splash, you'll get have cuckoo and half blue cuckoo. Or if you do it the other way around with a Splash roo on Cuckoo hens, you'll get sexlinks, the males will be blue cuckoo and the hens will be blue.
If they said they got the Blue Marans directly from Barber, they are lying.....Mr Barber has been dead for quite some time. I do not think he ever had Blue Marans imported here in the US. I think the Blue Marans was created here in the US some time ago, very quietly.
I never heard of Bleu Marans, probably another added "new" breed name for the crosses they are trying to establish. Blue Marans, yes.