| Gold won't tarnish, rust, or corrode, and though it's very strong, it is also the most malleable of all metals. Gold in its pure form (24k) is too soft to withstand abrasions caused from extensive daily wear, so it is alloyed with other metals to give it strength. This strength makes gold an excellent choice for a ring setting. Common gold alloys are silver, copper, nickel, and zinc.
Gold colour is determined by the percentage of alloys that are included in the metal. When gold is alloyed with silver, copper, and zinc, the shade of colour will vary. When gold is alloyed with nickel, copper, and zinc, it becomes white gold. Yellow gold and white gold have very similar strength and malleability. White gold looks very similar to platinum, but the two have very different properties and prices. ow do you know it is real gold?
When purchasing an item of gold jewellery, always look for a carat mark which should be stamped on it. This is a quality mark and refers to the proportion of pure gold in the item. Pure gold, which is 24ct, the metric equivalent being 1000, is generally considered too soft for practical uses in jewellery and is alloyed with other precious and base metals to increase its durability. Some of the common markings found on jewellery, with their metric equivalents, are:
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22ct or 916 |
18ct or 750 |
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14ct or 585 |
9ct or 375 |
Some other precious metal markings on jewellery are:
Silver - sterling or 925, Palladium - Pal, PD or 900
Platinum - Plat, Pt or 950
Markings on jewellery items are not limited to the carat or quality mark. You may find a manufacturer's trade mark, logo or initials on some jewellery, particularly items made in the United Kingdom where a comprehensive hallmarking system is in place.
Care of gold jewellery
Like all jewellery, gold should be periodically cleaned and checked for wear and breakages. You can clean it yourself with warm, soapy water, but your jeweller can re-polish it and add that extra sparkle. Also, store your jewellery so that items don't scratch or scuff each other. Perhaps use a jewellery box, with separate compartments, stored in a secure place.
"I can't wear gold ... it leaves a black mark"
Jewellers often hear this complaint. They call it "the mystery of the gold smudge". Under normal conditions gold won't tarnish or corrode, but there are generations of stories about "not being able to wear gold." Research into the "gold smudge" has five basic reasons why gold can sometimes leave a black mark or a rash.
- Sometimes skin secretion and perspiration contain chemicals which react with the molecules of other metals in the gold alloy. This can happen when changes occur in body chemistry for example, during pregnancy.
- Outside chemical influences, such as medications, cosmetics, hairsprays and perfumes may sometimes be to blame for the "smudge." Always allow these products to dry before putting on your jewellery. Some shampoos, for example, those produced specifically for dandruff or scalp problems may leave a residue on the skin that will continue to tarnish lower carat gold.
- Air pollutants from industry may cause the "smudge" which can rub off onto the skin when jewellery is worn.
- Minute particles of dust or powder may be embedded in the skin which can result in extremely small particles of gold alloy being rubbed off and left on the skin.
- The fifth and least likely cause may be an allergy to gold or one of the other metals in the alloy, such as an allergy to nickel which is commonly used in fashion jewellery, some white golds and some modern hard gold-plating methods.
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