Antique or foreign white gold ring?

by Rachel
(Sammamish WA USA)

I have a 'mother's ring' that has 5 stones and is hallmarked inside as follows: a shield with w/s inside it (w on upper portion then a slash or slanted line, then the s on lower portion. There is also what looks like a 'cf' in an oval circle and a '52' in an oval circle right next to it. There is also a 'vn' on the other side of the shield.

This looks & feels like white gold but I have no idea about these hallmarks??? Thank you, Rachel P.S. T

The discoloration on the ring in the picture is from my lamp~