Really subtle blues then maybe? I think one of the ones I originally thought was a chocolate might be a black and I am not 100% convinced the white one is actually white, it seems kind of creamier than the yellow parts on the other ducklings *shrugs* gonna have to wait and see
Yes it is a grey looking marking usually when the duck is grown folks often confuse the silver with a lavender especially if the lav is light colored. Yours looks to be very pale and should be beautiful. A solid white is near to impossible to get because of the required recessive white genes and the Anconas are so colored heavy in gene makeup it would be a one in a 1/2 million odds if possible at all.
Scroll down the ancona pics and you will see a silver....this is Aurora Springs' website