Gemstone Care Guide


kunzite pendant - gemstone care guide
Kunzite, a variety of spodumene, ranges in color from pink to lavender. It can lose its color if exposed to sunlight for even a few hours. “New Pendant Kunzite” by topzhang. Licensed under CC By 2.0.

Consult our gemstone care guide to learn the best cleaning methods for many popular gems. Most will respond well to warm water, mild detergent, and a soft brush at home. However, some gems do have sensitivities. Familiarize yourself with these, particularly if you decide to have them cleaned mechanically, whether at home or professionally.

GemstoneCleaning TechniquesComments
AmberDamp cloth and dry. Warm water and detergent is also effective.Amber is an organic gem, sort of a fossilized and hardened form of resin from ancient pine trees.
AmethystWarm water, detergent, and soft brushMost amethyst is heat treated to bring out best color, but it can crack as well as fade if exposed to high temperatures.
AquamarineWarm water, detergent, and soft brushThis blue beryl also receives heat treatments to bring out its blue color. Heat can still cause color fading.
CarnelianMoist cloth. Rub briskly with dry cloth.Since wax won’t adhere to this tough variety of quartz, ancient people famously used this material to make seals.
CitrineWarm water, detergent, and soft brushThis heat-treated quartz will fade when exposed to heat.
CoralDamp cloth and dry.Another organic gem, made from the exudations of tiny marine animals. Extremely sensitive to flame and heat.
DiamondAmmonia-based cleaner. Warm water, detergent (grease cutting), and soft brush. Mechanical cleaning systems. (See Comments).Diamonds have the greatest hardness of any natural material, which means they resist scratches better than any other gem. These stones take heat well, too. However, mechanical systems could pose a danger if a stone isn’t examined well beforehand. Although resistant to scratches, diamonds are susceptible to damage from physical blows. To maintain brilliance, remove any grease.
EmeraldWarm water, detergent, and soft brushMost emeralds are routinely bathed in warm oil after fashioning to improve color. Sometimes, dyes are added. Mechanical systems could boil out the oil. Inclusions in emerald often weaken the stone. Thus, mechanical systems can potentially cause breakage.
GarnetWarm water, detergent, and soft brushAlthough relatively hard and tough, garnets do have some heat sensitivity.
HeliodorWarm water, detergent, and soft brushThese yellow beryl gems tend to be reasonably hardy and tough. However, avoid temperature extremes.
IvoryWipe clean with damp cloth and dry. Warm water, detergent, and soft brush also work well.This organic gem material, consisting of calcium phosphate, sometimes receives harsh dyes. So much so that chemical cleaning could impair its appearance.
JadeWarm water, detergent, and soft brush. Mechanical cleaning systems. (See Comments).Both jadeite and nephrite are tough with little to worry about. They may withstand mechanical cleaning. However, acid treatments to improve color may weaken some specimens. Have a professional gemologist examine any pieces to identify treatments. Both jade varieties can take a high lustrous polish. Re-polishing requires professional equipment.
KunziteWarm water, detergent, and soft brushThis spodumene variety has a distinct cleavage plane, which opens with little impact. Sunlight causes its lavender color to fade. This is definitely a “night stone.”
Lapis lazuliWarm water, detergent, and soft brushThis porous material can vary greatly in appearance. It often receives dyes to improve color.
MalachiteCool water, detergent, and soft brush.Polishes bright but wear can cause finish to dull. Rub briskly with wood to help restore finish. Sensitive to acid, ammonia, heat, and hot water.
OpalWarm water, detergent, and soft brushVery sensitive to pressure and thermal shock (hot or cold), which causes crazing (surface cracking). This soft and fragile gem requires special care. (Follow the links at the end of this article).
PearlWipe with damp, soft cloth. Remove stains with a mild soapy solution on a rag. Don’t dip pearls into liquid. Dry thoroughly. Blow out drill holes carefully. Moisture trapped there often causes discoloration.These organic gems require special care to look their best. (Follow the links at the end of this article).
PeridotWarm water, detergent, and soft brushAcids (even from perspiration) and heat can damage peridot stones. Wear with care and protective settings, since surface scratches will diminish this gem’s finish.
jade, lapis, and pearl jewelry - gemstone care guide
“Lapis, Pearls, and Jade Necklace and Earrings with Vintage Filigree Accents,” natural grey saltwater pearls, by Naomi King, Starlite Jewelry Designs. Licensed under CC By 2.0.
GemstoneCleaning TechniquesComments
RubyWarm water, detergent, and soft brush. Mechanical cleaning. (See Comments).More and more rubies receive oil treatments. Be aware that mechanical cleaning could remove this oil. In addition, high heat could damage gems with many crystal inclusions.
SapphireWarm water, detergent, and soft brush. Mechanical cleaning. (See Comments).Sapphire, like ruby, is gem-quality corundum. Thus, it generally receives the same treatments as ruby, so the same care advice applies. This gem may receive oil treatments, and inclusions may weaken its normally tough structure.
SpinelWarm water, detergent, and soft brush. Mechanical cleaning.Hard and durable, spinels should give you little trouble. They hold their beauty over time.
TanzaniteWarm water, detergent, and soft brushHeat treatments create this gem’s stunning blue color. Tanzanite is fragile, relatively soft, and sensitive to heat and vibrations.
TurquoiseWipe with damp cloth, then wipe dry immediately.Avoid cleaning this porous gem material with soap, detergents, or cleaning solutions. They tend to penetrate the material, thus turning it green and/or an unattractive off-color blue.
TopazWarm water, detergent, and soft brushEasy cleavage makes mechanical cleaning relatively dangerous for topaz. Both vibrations and heating may damage these gems. Jewelry stones may also have stress points from prongs due to improper settings.
TourmalineWarm water, detergent, and soft brushAlthough reasonably hard gems, tourmalines tend to be brittle. The pink variety is often flawed and could be structurally weak, thus vulnerable to vibration damage. These gems are moderately sensitive to heat. Bi-colored crystals sometimes split at color junctures.
ZirconWarm water, detergent, and soft brushProne to impurities, zircon can be affected by heat extremes. Nevertheless, fine blue and white zircon is heat treated.

Gemstone Care Series

topaz ring - gemstone care guide
“Topaz Ring,” blue topaz and 950 silver, by Mauro Cateb. Licensed under CC By 2.0.

About the author
Dr. Gerald Wykoff GG CSM
Dr. Gerald Wykoff is GG (Graduate Gemologist), a CSM (Certified Supreme Master gemcutter), educator, and author of several gemology books. He founded the American Society of Gemcutters in the 1980s and served for more than 10 years as the editor of its monthly magazine, American Gemcutter.
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