Yes. It is safe and effective on all metals and gems including soft, porous stones like pearls and opal. Our jewelry cleaner can even be used on costume jewelry and doesn't contain any acids that will break down glue, and is safe for use on antique jewelry pieces as well. The only exceptions are Amber and Ethiopian Opal. Since Amber is a resin material and not a gem, it should only be cleaned with a soft cloth. Ethiopian opal is, meaning it absorbs water, which can lead to instability and crazing. Any moisture could contribute to problems and should be avoided with Ethiopian opals.