I think you'll need to stick with white because Ameraucanas are generally recessive white which means he could carry any number of colour genes. I have a white Amer roo and his first batch of babies are in the brooder now. Here's what I've gotten from him:
BBS hens - babies that looked blue & black at hatching but are developing some buff coloration on their feathers (e.g. blue with buff, black with buff). Some still look solid black (2 weeks old).
Buff hen - one black with buff colored head & wings (no idea what color the body feathers are going to be), one yellow/slightly buffish chick feathering out whitish/greyish buff, and one pale greyish chich with buffish head feathering out pale greyish/buffish.
White hen - yellow/white babies.
EE hens - wide variety of chipmunk babies, many feathering out with buff tones.
So it looks like my boy carries blue and buff and who knows what else ...