Often, jewellery and gemstones are more fragile than other types of antiques. It’s still relatively easy to prevent damage once you know what not to do.
Fragile gemstones or crystal beads shatter if hit against a hard surface. A soft, 18-carat gold ring wears paper-thin if worn constantly, especially if it lies next to another ring of harder metal.
It is asking for trouble – in the form of damage or loss – if you wear jewellery while doing domestic work. Immersion in hot water won’t affect a diamond, but it could split in two if knocked hard. Emeralds, sapphires, aquamarines and opals may well shatter on exposure to even hand-hot water.
The colour of stones such as topaz and turquoise changes with prolonged exposure to strong light; opals chip and crack very easily when exposed to heat; and pearls may lose their lustre and yellow or darken if they get too dry. Ivory cracks easily in heat, sunlight, or a dry atmosphere. Base metals usually make up costume jewellery. Brass and copper may corrode, and simulated stones may gradually fade over time.
Settings & Fastenings
To guard against loss, regularly check that chain links, fastening and settings are secure. Clasps weaken with constant use, and sharp edges on beads fray the thread. If you have any pearls, you should wear them. The lustre improves as pearls absorb natural oils from the skin. Check them every six months, and have them professionally restrung if necessary, with strong, purpose-made necklace thread, knotted between each pearl both to prevent the beads rubbing against each other and to guard against all the pearls scattering if the string breaks. Securely pin heavy brooches into sturdy material (if necessary, into the strap of an undergarment), and consider safety chains as an option.
Hairspray and perfume
Apply hairspray and perfume before you put on your jewellery. These substances usually contain alcohol or chemicals which act as solvents or chemical reagents on certain materials, including plated gold, mother-of-pearl, amber, jet, coral and on porous gemstones such as turquoise, opals and pearls.
Avoid mixing different types of jewellery in one box. Jumbled up with harder materials, softer materials chip. (Examples of softer materials: precious stones, glass, jade, shell cameo, ivory and enamel.) A hard, sharply cut stone like a diamond will scratch gold, silver, and softer stones.
Necklaces and strings of beads can be hung or wound around a roll of acid-free paper to prevent tangling. Otherwise, keep each item of jewellery in its own box, or wrap it separately in clean, acid-free tissue or soft, pure cotton or linen cloth.
Knowing the materials in a piece of jewellery is vital before cleaning. If you’re unsure, check with a jeweller who works with antique pieces. A professional should clean Ancient jewellery, as age and the softer metal used means it’s very fragile.
Do not immerse porous stones (opals and pearls, etc) in water; they will lose their natural lustre. A soft jewellers’ cloth (available from a jewellers’) will gently buff most metal jewellery. You can also wipe the item with a very slightly dampened chamois leather.
Remember that plated and rolled gold wears away if rubbed too much. Do not polish the matte finish gold found on some 19th century jewellery.
If wet, the thread of a strung necklace or bracelet will shrink and eventually rot. Dampened cotton-wool buds will clean water-resistant beads individually. Enamel is very delicate and should only be dusted gently or blown clean. Ivory, too, should only be cleaned with a dry, soft-bristled brush as it absorbs water and stains; for ingrained dirt go to an expert.
Stones in a closed setting should not be allowed to get wet as water may lodge behind the stones and trigger corrosion, or weaken any adhesive. Clean instead with a cotton wool bud dipped in clear pure alcohol, then rinse and dry with cotton buds.
Immersing in water
If you are confident that a piece can be safely immersed in water, do not risk losing it for ever by washing it over an open sink or plughole. Instead put some lukewarm water with a few drops of mild or non-ionic detergent in a small bowl. Place this on a tray with raised edges and covered with a towel or cloth. Immerse the item in the water and very gently ease out the dirt with a soft-bristled brush, or a wooden cocktail stick for stubborn grime in small areas. Rinse the jewellery in a separate bowl of clear water and allow it to dry naturally on a piece of absorbent kitchen paper. Cameos, jet, gold and silver items can be cleaned in this way.
A reputable jeweller used to working with antiques should carry out jewellery repairs. At the same time, an overall check of settings and clasps. If you want to glue an item of jewellery yourself – a hard gemstone, for example – remove any old adhesive first and remember that the repair is unlikely to be easily reversible.
With thanks to Readers Digest.
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