My diamonds have lost their sparkle, I wear them all the time and don't take them off so there's probably a build up of soap, sun cream etc, I have a sonic cleaner and have tried cleaning them with a toothbrush but it's not made much difference, the platinum looks scratched and I think needs a good polish with a machine. Wonder how much a jeweler might charge to clean a ring, necklace and stud earrings? Do other people take off their jewellry when bathing, cleaning, applying hand cream etc?