It prolongs the life, especially jewelry like earrings and bracelets with moving parts. It looks better and you'll feel better too, you'll be just as sparkly as your jewels! You can clean almost everything at home, but be sure to see your jeweler for professional cleanings and the ever-important safety check at least yearly.
Do clean gold and platinum and gems with warm water, a few drops of ammonia and dawn dish detergent. Scrub with an old soft toothbrush. Rinse and pat dry.
DO NOT SOAK pearls, opals, emeralds or turquoise.
Only clean pearls with a soft cloth, and check the silk string, it wears out. If you see stretched or dirty string, it's time to have them re-strung by a pro.
Do clean pearl studs (posts) with a bit of the cleaning liquid, just don't soak and be sure to rinse quickly.
See your jewelry professional if you have any questions, and remember a cleaning is usually free!