Is it real silver? If it's silver overlay or sterling silver, use Heggarty's silver polish. It comes in a blue spray can. If you use it, DON'T follow the directions on the can! They say to spray it on the silver directly from the can! They didn't anticipate it being used on a saddle! The overspray would stain the leather.
Instead, spray on a bit of towel, then rub the silver.
You can get it at Schneider's.