Dishwater

A young bride and groom-to-be had just selected their wedding rings. As the young lady admired the plain platinum and diamond band she had chosen for herself, she suddenly looked concerned.
“Tell me,” she asked the rather elderly salesman, “is there anything special I’ll have to do to take care of this ring?”
With a fatherly smile, the salesman said, “One of the best ways to protect a wedding ring is to soak it in dishwater.”