Bantam Orpingtons - Black Rooster x Blue hens = what colour offsprings?

[Chook mumma]

From pedigree bred stock, black x blue, I've had this little one hatch. It certainly isn't a black, and doesn't have even the slightest blue tinge to suggest Blue or Splash, so what colour adult can I anticipate? I was expecting mainly blacks, some blue and maybe a splash. Any idea?

BTW the pics were taken to observe early wing feather growth to see if it's true that the first growth pattern can be an early indicator.

Thanks to anyone who can help.

 

[Poultrybonkers]

The adults are carrying recessive white is my guess

 

[Stacaroni]

Huh. Maybe we are outside the realm of BBS...

 

[The Moonshiner]

Black crossed with blue should give you about 50% black and 50% blue. No splash.
Yes both parents must be carrying a recessive white gene. That pairing should continue to produce about 25% white offspring.