Antique Silver Rings How Can I Tell If My Ring Is Actually White Gold Rather Than Silver? Or Is It Platinium? It's An Antique.?

How can i tell if my ring is actually white gold rather than silver? or is it platinium? it's an antique.? - antique silver rings

I bought it in Austria and has (a diamond in my engagement ring to him ...) I thought it was white gold, because what they store in those, but I is my "new" covenant white gold 18 months and the wedding ring a slightly yellowish color, while the silver ring Engagem still promising .... What could it mean, it's money? or is it just a better quality of my gold ring wedding white? Please help - I do not want to get back to a value for the loss!