Pearls become yellow over time when they are not properly cared for, have been allowed to dry out, or are frequently worn. This can be the result of brittle nacre, or from a build up of sweat and oil from the skin. However, there are a few things you can do to whiten yellowed pearls and enhance their natural beauty and luster.
Things You'll Need
Combine 1 tbsp. of mild liquid hand soap with 1 cup of warm water in a small bowl. Stir it well to combine. Mild dish soap may also be used.
Place the yellowed pearls into the soapy water and use a soft cotton cloth to clean them gently. Do not scrub them, but rub away any dirt or debris delicately.
Remove the pearls from the soapy water and rinse them in a fresh stream of cold tap water from the faucet. Dry the pearls well with a clean, dry cotton cloth.
Dampen another cotton cloth with acetone nail polish remover. Wipe the pearls gently with the dampened cloth to strengthen the nacre and revive your yellowed pearls.
Lay the string of pearls in direct sunlight in a window sill or any other safe place where they will receive full sun. Allow them to remain for several hours, and repeat daily as necessary. It may take several sunlight treatments before you notice visible changes in color.
Wrap the pearls in a linen or soft cotton cloth after each treatment. Or use and store them away from other jewelry. Do not place them in an airtight container, as they need moisture to retain their white color and prevent cracking.
Even by performing the above steps to whiten yellowed pearls, they still may not return to their original color. However, these techniques will significantly enhance their whiteness.