How to Clean Gemstones Without Dulling What Makes Them Glow

Curated by Sophia Jewelers · November 4, 2026 · 10 min readGemstone Guide

The ring looked brighter the day it came home. Nothing has happened to the stone since. A thin film of hand cream and soap has settled behind it, right where the light used to come back out, and for most stones a bowl of warm water will clear it in fifteen minutes.

Knowing how to clean gemstones comes down to one habit: find out what the stone can take before it gets wet. A sapphire can sit in a soapy bowl for a quarter of an hour. An opal should not, and the ultrasonic machine that leaves a diamond sparkling can crack an emerald.

Most of the jewelry box needs nothing fancier than dish soap and a baby toothbrush. The exceptions are few, and they are worth learning by name.

Why Gemstones Go Dull Between Cleanings

Light enters a faceted stone through the top, bounces off the angled facets inside and returns to your eye. Coat the underside with lotion or skin oil and the light leaks away instead of coming back. That is why a quick polish across the top changes so little. Most of the grime sits underneath, tucked behind prongs and under the stone where a cloth never reaches.

Rings have it hardest, since they go through every hand wash and every jar of cream. A halo like the one above gives that film plenty of small corners to settle in. Earrings and necklaces pick up hairspray and perfume instead, and bracelets collect a little of everything in their links.

Three Questions to Ask Before Any Stone Gets Wet

How hard is it? The Mohs scale measures how well a stone resists scratching. Ordinary household dust contains quartz, which sits at 7, so a gritty cloth can slowly haze anything softer. Our gemstone hardness guide sets out the full list and explains why a hard stone can still chip.

Does it have fractures or pores? Emerald is hard but threaded with tiny fractures. Turquoise and pearl absorb what touches them, and opal holds water inside its structure. Stones like these dislike heat, vibration and long baths, whatever their hardness number says.

Has it been treated? Oil, resin, dye and glass filling can all react badly to cleaners and heat, and many colored stones carry some treatment. Our guide to treated and untreated gemstones explains what to look for. Lab-created ruby and sapphire share the chemistry and hardness of mined stones, as we cover in natural vs synthetic gemstones, so they follow the same rules.

Keep this chart near the sink. These are the usual limits for undamaged stones in sound settings. When a treatment is unknown, follow the gentler answer.

Stone	Mohs hardness	Warm soapy water	Ultrasonic	Steam
Diamond	10	Yes	Usually safe	Usually safe
Ruby and sapphire	9	Yes	Usually safe if not fracture filled	Usually safe if not fracture filled
Topaz	8	Yes	No	No
Aquamarine	7.5 to 8	Yes	Ask a jeweler	No
Emerald	7.5 to 8	A quick dip only	No	No
Amethyst and citrine	7	Yes	Usually safe if not dyed	No
Garnet	6.5 to 7.5	Yes	Usually safe	No
Peridot	6.5 to 7	Yes	No	No
Tanzanite	6 to 7	Yes	No	No
Opal	5.5 to 6.5	Damp cloth	No	No
Turquoise	5 to 6	Damp cloth	No	No
Pearl	2.5 to 4.5	Damp cloth	No	No

How to Clean Gemstones With the Warm Water Method

You need two small bowls, mild dish soap, a soft baby toothbrush and a clean lint-free cloth. Then:

1. Look the piece over first. If a stone shifts or a prong has lifted, stop and take it to a jeweler, because a soak can free a stone that was barely holding on.
2. Fill one bowl with water that feels comfortably warm on your hand, and stir in a few drops of soap. Fill the second with plain water at the same temperature.
3. Let the piece soak for ten to fifteen minutes. The soak does the hard part.
4. Brush gently behind the stone and around the prongs, where the film collects.
5. Swish it through the second bowl. Rinsing there means no ring ever meets an open drain.
6. Pat it dry with the cloth, then let it air dry fully before it goes back in the box.

Sapphire and ruby love this routine. At 9 on the Mohs scale they are also among the best gemstones for daily wear, so they tend to need it most. Aquamarine, amethyst, citrine, garnet and topaz handle it well too. For tanzanite and peridot, we would shorten the soak to a few minutes and avoid any sudden change of temperature.

The studs below show how little there is to it. Each pair sets a 4mm stone in 14K white gold, and a soft brush reaches the back of a stud easily. For a ruby or sapphire earring worn most days, a monthly bowl of soapy water is plenty.

Emerald, Opal, Pearl and Turquoise Ask for a Lighter Hand

Emerald

Most mined emeralds are filled with oil or resin to soften the look of their fractures. Heat, solvents and vibration can draw that filling out, and the fractures then show more clearly. Dip the piece briefly in lukewarm soapy water, brush the setting lightly, rinse right away and dry. We clean lab-created emerald the same careful way.

Opal

Opal holds water in its structure, and a sudden swing in temperature can crack it. At 5.5 to 6.5 it scratches easily too. Wipe it with a soft damp cloth, using a touch of mild soap if it needs more, and dry it straight away. Opal doublets and triplets deserve extra care, since each is a thin slice of opal glued to a backing, and water can work its way into that glue.

Pearl

A pearl is built from layers of nacre, and nacre is mostly calcium carbonate, which is why vinegar and lemon juice etch it. Wipe pearls with a soft damp cloth after each wearing to lift skin oil and perfume. Keep strung pearls out of the bowl altogether, because wet silk stretches and weakens. Lay a damp strand flat until it dries. Our guide to choosing pearl jewelry covers the rest of a pearl's needs.

The stones most likely to be ruined are usually the ones somebody was trying hard to look after.

Turquoise

This stone is porous, and at 5 to 6 on the Mohs scale it sits below the quartz in household dust. Over the years it can soak up skin oil, soap and cosmetics, and its color may shift as a result. A damp cloth and a dry cloth are all it needs. Put turquoise on last, after your lotion has sunk in, and wipe it when it comes off.

The bracelet below sets cultured freshwater pearls in 14K yellow gold, and the star studs are polished turquoise in the same metal. Both stay happiest with a cloth and a short wipe after each wearing.

Ultrasonic Cleaners and Steamers: Which Stones Can Take Them

An ultrasonic bath sends high frequency vibration through liquid, and that vibration shakes grime loose. It can also shake a weak prong or widen a fracture. A steamer adds heat and pressure. Both clean well on the right piece. On the wrong one, the damage is permanent.

Diamond, along with ruby and sapphire that have not been fracture filled, can usually go in either machine when the setting is sound, and our guide to cleaning diamond rings covers that routine. Amethyst, citrine and garnet can often take an ultrasonic bath, but steam's heat is a risk for them. Emerald, opal, pearl, turquoise, tanzanite, topaz and peridot should stay out of both.

Topaz and tanzanite catch people out. Topaz reaches 8 on the Mohs scale and tanzanite sits at 6 to 7, yet both can split along internal planes when shaken or heated. A mixed piece follows the same logic, so go by its most delicate stone.

Household Cleaners to Keep Away From Your Stones

The internet loves a kitchen remedy. Most of them were meant for something else.

Toothpaste contains abrasives, and baking soda paste scrubs in much the same way, so both can haze softer stones and scratch polished gold. Chlorine bleach attacks the alloys in gold and can weaken prongs over time, which is one more reason to take rings off before the pool, as our note on wearing jewelry in the shower explains. Vinegar, lemon juice and ammonia may brighten a diamond, but they can harm pearl, opal, turquoise and treated stones.

Boiling water belongs on the same list, along with chemical jewelry dips made for one metal or stone. Paper towels and tissues can carry grit, so reach for a clean microfiber cloth instead. For the metal around the stone, our guide to cleaning gold jewelry has the detail.

How Often to Clean, and When to Call a Jeweler

Our rule of thumb: a ring worn daily gets a wash every week or two, and earrings and pendants get one about once a month. Pearls get a wipe every time they come off. The rest of the routine lives in our gemstone jewelry care guide and our guide to storing jewelry, since a clean stone still scratches against a harder neighbor in the box.

Book a jeweler once a year to check prongs and settings, and sooner if a stone rattles or a clean leaves it still looking cloudy. Ask them to handle any deep cleaning on emerald, and any question about re-oiling. Our jewelry maintenance checklist keeps those dates in one place.

Some pieces ask almost nothing of you. The amethyst heart necklace below hangs on a 15 inch chain, and the garnet studs set a round 4mm January stone. Both are 14K yellow gold, and both come out of a soapy bowl looking newly bought.

Back on the Finger by Morning

Pick an evening this week. Set out two bowls, take off the ring you have stopped noticing, and give it fifteen minutes while you do something else. Pat it dry and leave it on a soft cloth overnight.

In the morning, hold it up to the window. When you are ready to add to the box, browse our gemstone jewelry and keep this chart close by.