How to Clean Diamond Jewelry at Home

• A small bowl of warm water, not hot. Comfortable on your hand is right.
• Mild dish soap without moisturizers, bleach or lemon scrubbing agents. A few drops is enough.
• A soft toothbrush, ideally a child's brush or an extra-soft adult brush kept only for jewelry.
• A lint-free cloth or a microfiber glasses cloth.
• A sink strainer or a closed drain. Rings slip.

That is the whole kit. GIA's own cleaning guidance lists warm water, mild soap and a soft brush as safe for most gemstones, and diamonds are the hardest of them, rating 10 on the Mohs scale.

1. Close the drain. Work over a bowl, never over an open sink.
2. Soak for 20 to 30 minutes. The soap loosens the film of skin oil, lotion and hair product that dulls a diamond.
3. Brush gently. Use small circles on the top of the stone, then turn the piece over and brush the back. Hold rings by the band, not the stone.
4. Rinse in a bowl of clean warm water, or under a slow tap with the drain closed.
5. Pat dry with the lint-free cloth, then let it air dry for a few minutes so no water sits under the setting.
6. Look at it under a lamp. If the stone still looks cloudy, repeat the soak; heavy buildup sometimes takes two rounds.

A diamond gets its sparkle from light that enters the top, bounces off the angled facets underneath and comes back out. When the underside, called the pavilion, is coated with oil and soap residue, that light leaks out the bottom and the stone looks gray. That is why a ring that looks dull from the top usually needs cleaning from the back.

On a solitaire, angle the brush up through the gallery, the open space under the stone. On halo and pavé pieces, brush with the bristles moving along the rows of small stones, not across them, so you do not catch a prong. Our round lab diamond solitaires, like the Round Lab Diamond Ring 1.5 ct ($2,000) and the Round Lab Diamond Ring 4.62 ct ($2,800), both E color and VS1 clarity, show the difference most: a clean pavilion is what makes an E stone look white and bright.

If a piece mixes diamonds with softer gems, pearls or enamel, clean it as if it were the most delicate material on it. Pearls, opals and emeralds should not soak.

Stud earrings: soak the earrings and the backs together, and brush the post and the base of the setting, where skin and hair product collect most. Dry the backs fully before putting them back on so they keep their grip.

Pendants: take the pendant off the chain, or clean both together if the chain is plain gold. Brush the bail, the loop the chain runs through, because it traps soap.

Tennis and pavé bracelets: lay the bracelet flat in the bowl instead of bunching it. Brush along the line of stones and dry it flat. A bracelet set with dozens of stones, like the Round Lab Diamond Bracelet 7.49 ct ($2,200), has dozens of prongs to catch lint, so a lint-free cloth matters here. For chains and pendants covered in small stones, follow our guide to cleaning iced out jewelry.

The annual visit is less about shine and more about safety: a jeweler checks prongs and settings under magnification. Read how often to check your prongs for the warning signs between visits.

Most of the dulling on a diamond comes from your own hands. Every time you touch the stone to check it, adjust it or turn it, you leave skin oil on the table facet. A few habits cut the cleaning you need in half:

• Pick rings up by the band, never by the stone.
• Put lotion, sunscreen and hair product on first, let them dry, then put your jewelry on.
• Take rings off to cook with oil, knead dough, garden or clean with household chemicals.
• Wipe the piece with a dry microfiber cloth when you take it off at night.
• Store each piece in its own pouch so dust and hard contact stay off it.

A ring treated this way often goes two or three weeks between soaks and still looks freshly cleaned.

Hand the piece to a professional when a stone moves or rattles, when buildup does not lift after two soaks, when the piece has a gem that cannot soak, or when you want steam and ultrasonic cleaning. A jeweler checks the settings first and only then puts the piece in an ultrasonic bath, which is the right order. Cleaning at home does not change a diamond's grade: clarity and color are fixed at the cutting wheel, as explained in our 4Cs guide and clarity chart. Lab-grown and natural diamonds clean the same way, since both are carbon crystals with the same hardness; see are lab diamonds real.