You could, or maybe wait until the chick grows some feathers (which will probably make things a bit more clear.)
A silver/gold split just has both of those genes, one on each of his two Z chromosomes.
Because females have chromosomes ZW, and silver or gold is on the Z chromosome, a female...
As regards the blue gene, correct. But it doesn't tell much about the other genes she has.
As regards silver/gold, you are probably correct that he shows silver and carries gold. Or he might be pure for silver but not have all the right genes to make a clean white color in the silver areas...