Try contacting a breeder in your area and see if they can give you a definition. In boers we have violet pigment that looks pink but has a slight gray tint. It can be hard to distinguish
I don't believe so. In skillathon (all livestolivestock knowledge including breed id) were taught all nubians are anglo-nubians... does a anglo nubian differ from a normal nubian? If not, then there is no color standard for nubians.