Can dutch bantams be color sexed?

[CalicoFarm]

I just hatched out 2 black tailed buff dutch bantams. They are both different colors, could they be a cock and a pullet?

 

[Sonoran Silkies]

Black tailed buff has no real colour variation between the genders, so no.

I am thinking, though that the greyish one may be a different variety. Are you sure both parents were btb?