Your pearls will sparkle like the day you got them with the right cleaning technique. Here's the safe way that jewelers recommend.
Wipe each pearl with a soft, slightly damp cloth after wearing to remove perfume, oils, and sweat.
Dampen a cloth with water and a tiny drop of dish soap. Wipe each pearl individually. Never submerge the strand.
Wipe again with a cloth dampened in plain water to remove any soap residue.
Lay the strand flat on a soft towel to dry. Never hang pearls wet -- moisture weakens the silk thread.