How to Clean Pearls Safely (and Why Not Baby Oil)

Pearls aren't stones at all. They grow inside a mollusk, and gemologists count them among the organic gems: soft, sensitive to chemicals, and unhappy with heat. That's why almost every cleaning "hack" you'll see is wrong for them.

In this guide I'll show you the simple routine the experts recommend, the things that harm pearls, and what to make of the idea of rubbing them with baby oil.

Soft, and sensitive to almost everything

GIA ranks pearl at 2.5 on the Mohs hardness scale, "very soft and easily scratched or abraded." And pearls react. GIA's warning is worth reading twice: "Pearl can be damaged by many chemicals and all acids. The list includes hair spray, perfume, cosmetics, and even perspiration." Mikimoto, the Japanese pearl house, adds that pearls are "vulnerable to acid, alkaline and extremes of humidity."

So pearl care is mostly about what you don't do.

The routine that works

Last on, first off. GIA: "Always apply perfume, hair products and cosmetics before putting on your pearl jewelry," and "pearls should be the last thing you put on and the first thing you take off." Mikimoto says the same.

Wipe after every wearing. "For routine care, it's best to wipe cultured pearls with a very soft, clean cloth after each wearing," says GIA. The American Gem Society (AGS) suggests a soft chamois or flannel cloth, to remove skin oils and salts. That small habit does more for pearls than any cleaner.

Wash rarely, and dry flat. GIA says warm, soapy water is safe "for occasional, thorough cleaning," but if the pearls are strung, "be sure the string is completely dry before wearing." It suggests laying the strand on a towel to dry. Don't soak it: AGS warns that a wet string "may stretch or break," and a jewelry insurer says submerging a pearl necklace will weaken the silk thread.

Never on pearls

• Ultrasonic or steam cleaners. GIA says pearls should never be cleaned in either.
• Ammonia, vinegar, lemon, bleach, silver dips and jewelry cleaners. "All acids" damage pearl, and GIA says porous gems such as pearl shouldn't meet ammonia-based cleaners.
• Toothpaste and baking soda. AGS warns against both.
• A silver polishing cloth. Pandora warns that it may dull pearls.
• Hanging a wet strand to dry, or wearing it before the string is dry.
• High heat or strong light. GIA warns that heat from intense light can cause dehydration and cracked nacre.

What about baby oil?

We found no gemological source that recommends rubbing oil on pearls. GIA warns that many chemicals and cosmetics damage them, and one insurer says plainly that "perfume, oils and lotions can also discolor pearls," with natural body oils as the exception.

The video above deserves credit here. Despite its title, it argues against baby oil, and calls an oiled shine "makeup." Instead it recommends putting pearls on last, wiping them after each wear, an occasional barely damp cloth with a drop of mild soap, never soaking, and breathable storage away from sunlight and bathroom steam. GIA and Mikimoto give the same advice.

Two details in it need a gentle correction. We found no reliable source for the figure that pearls are "2% to 4%" water. And maeshori isn't a home soak in distilled water. GIA describes it as a factory pre-treatment that involves "immersing the pearls in a solvent, usually methyl alcohol," and the Japan Pearl Promotion Society defines it as immersion in water or organic solvents to improve luster and color. It isn't something to try at home. The video's conclusion stands: the habit, not the bottle.

The string, and where to keep them

Silk doesn't last forever. GIA explains that the string "can darken, stretch, or wear thin over time," and recommends knots between pearls, so they don't rub and so that, if the string breaks, you lose only one. How often to restring? GIA says once a year for pearls worn often; one insurer suggests every two to three years. When in doubt, ask your jeweler to check the string.

Keep pearls in a soft pouch or case, apart from other jewelry, and not in dry, hot places. GIA says: "Never store your pearl birthstones in a plastic bag," because plastic can emit a chemical that damages their surface. And Mikimoto offers a gentle reason to take them out: "There is a saying that 'pearls want to be worn.'" It warns that leaving them in a security box for long periods "may cause pearls to dehydrate."

Volume V, Clean It Right, covers pearls together with coral, amber and the other living gems, explains when a piece needs a jeweler instead, and checks the popular cleaning tricks against GIA, the American Gem Society and museum conservators.