About your silver plated ring you want to cut and solder. My
advice is a big bottle of aspirin. But, if you must…
Plating generally burns off in a typical soldering operation.
One way you can do it is with Tix (brandname) solder. However,
it isn’t as strong as traditional solder (4300 psi), so remove
your band material from a place where there will be the least
amount of stress. This is usually on the side, not the bottom.
The base metal is most probably brass.