Gemstones can be easily damaged, destroying their beauty and value, when improper cleaning methods are used. Your precious vintage gems can become beautiful heirlooms when they are cared for and cleaned properly. Take your valuable jewellery to a trained professional once a year to be inspected for signs of damage and given an expert cleaning. Between professional cleanings, there are some things you can do to keep your gemstone jewellery looking its best.
Always remove jewellery before bathing, washing dishes, or cleaning; soaps and detergents may leave a dulling film on the surface. Make-up, lotions, face/body powder, and skin oils may also leave a residue. Avoid exposing gemstones to household cleaners, solvents, hair coloring agents, hair sprays, and other chemicals which may cause some gems to lose their luster. Remove jewellery, especially rings, before doing any heavy lifting, yard work, engaging in sports, or other such physical activity, to avoid any scratches or other damage. When storing your jewellery, take care that the pieces do not rub against one another to avoid scratching.
There are two types of gemstones, transparent and opaque. The safest method of cleaning transparent gemstones is to wash them in warm water with a mild detergent. You may use a toothbrush or other soft brush to gently remove residue. Rinse well with lukewarm water and dry with a soft cloth. Opaque gemstones may be wiped with a damp, soapy, soft cloth, but should never be submerged. Liquid jewellery dips are not recommended for cleaning gemstones; most contain ammonia, which can damage the gem.
Some gemstones may lose color or crack when exposed to heat or sudden temperature changes, especially gems that have many inclusions. Those particularly susceptible to heat, temperature changes, or direct sunlight are emeralds, opals, moonstones, peridot, lapis lazuli, turquoise, tourmaline, and topaz. Steam cleaners available for home use are not recommended for most gems, but the method is considered excellent for diamonds.
Ultrasonic cleaners work by bombarding the jewellery with sound waves which knock the dirt off. Diamonds are generally safe to clean with this method. Rubies, sapphires, and emeralds should not be put into an ultrasonic cleaner. Do not put transparent gemstones that are prone to cracking in an ultrasonic cleaner, and never use an ultrasonic cleaner, ammonia, or chemical solutions to clean jewellery that contains opaque gemstones. These gems have a porous surface which may absorb the chemicals into their interior and cause the stone to discolor or crack. Before cleaning vintage jewellery, check to see that the stones are secure in their settings, since the ultrasonic vibrations may cause the gem to fall out. Use a toothpick to check for movement. If the gemstone wiggles in its setting, take the piece to a jeweller to have the prongs tightened before cleaning.
Pearls require delicate care when cleaning. Always use a mild detergent with warm water and a soft cloth. Alcohol or other chemicals can easily damage the layers of nacre. Never immerse pearls because the solution can get into the drilled holes and cause discoloration from within, and cause the thread to weaken. Clean the knots between the pearls carefully. Blow out any moisture that may accumulate from the holes and dry the strand on a lint-free cloth. Pearls should be restrung regularly, depending on how often they are worn, and should be stored away from other jewellery in a moisture-free environment. Do not keep pearls in a sealed plastic bag because any condensation may discolor them.
Cubic Zirconia (CZ) gemstones have become a fashion staple since their commercial introduction thirty years ago. They are created from the mineral zirconium oxide (not to be confused with zircon), rarely found in nature but widely synthesized in laboratories. When cleaning is necessary, you may use a mild dishwashing liquid mixed with a little water, and a soft brush, but be sure to rinse the gem well and dry thoroughly with a soft cloth. Ultrasonic or steam cleaners may also be used and will not damage the stone.
When in doubt about the best cleaning method for an especially dirty gem, or if the gem is particularly valuable or an heirloom, cleaning may best be left to a jeweller. The small cost is preferable to damaging your lovely jewellery with home cleaning methods.