I know that a 1:1 ammonia/water solution works wonders on gold and diamond from cleaning my e-ring... my issue is an antique ring that was given to me by my FI's grandmother. It's been handed down several times so it's a bit tarnished, but I don't know if it's made of silver or white gold. Some websites say that ammonia is good for cleaning sterling silver, but others say that it damages the silver. I'm looking for some sort of made-at-home solution that will clean both kinds of metals. Does anyone have suggestions on what to use to for this ring?