Info & facts

In the jewellery industry, gold, platinum and silver are known to be precious metals. Technically, the term precious metals refers to metals that are stable in air and not subject to oxidation. This is strictly true of gold and platinum. Silver, though tarnished when exposed to sulfur, is included because of its widespread use in jewellery.

In it’s pure form, gold is a shiny yellow metal. It is soft and easy to work with. With a specific gravity of 19.4, it is one of the heaviest of the common metals.

    Pure gold items easily deforms because of the softness and pliability of the metal. In response to this dilemma, gold alloying or the process of combining secondary metals with gold, was developed; and has a distinct effect on the colour, temper and hardness of a gold item. The alloying elements include, silver, copper, platinum and palladium. Pink and yellow gold is made by mixing silver or copper with pure gold. The better quality alloy white gold is a combination of pure gold and platinum metals such as palladium. In 9K white gold, silver is also added and red gold includes copper in the alloy.
    In the carat system pure gold is expressed as “24 carat fine” (24K). The K value expresses how many parts, by weight, of pure gold are contained in 24 parts of the alloy. 24K essentially means 100 percent (or fine) gold. The most popular jewellery gold used in South Africa are 9K, 14K and 18K where 9K refers to 9/24 or 37.5% pure gold, and 18K refers to 18/24 or 75% pure gold.

Platinum is a metal with a naturally white colour, where white gold is specifically an alloyed metal.

  • The platinum group consists of six metals including: platinum, palladium, rhodium, iridium, osmium and ruthenium.
  • It has a very high melting point of 1773°C. Platinum is a popular metal for creating fine jewellery because of its many desirable properties: It is soft, ductile, easy to work with and the metal itself is highly resistant to tarnish and corrosion.
    When purchasing jewellery, consider the purpose for which it is to be used. If you wish to wear a chain or a pair of earrings every day, semi-hollow jewellery should not be chosen. Solid jewellery can be worn more regularly. Avoid situations where your jewellery might be scratched or knocked. Apply perfume, hairspray and makeup before wearing any jewellery. Direct contact might lead to tarnishing. A higher percentage alloy like 9 carat gold tends to tarnish more easily than 14 or 18 carat gold. Never expose your jewellery to bleaches or abrasive materials. It is best to remove your jewellery before strenuous activities to avoid additional wear and tear, or possible breakage.
    Clean your jewellery regularly in a mild solution of one part ammonia, 1 part mild dishwashing liquid and six parts water. Dip your jewellery in the solution (or soak for 30 minutes when truly dirty and dull), scrub gently with a soft brush, rinse in clear water and dry with a lint-free cloth. Alternatively, jewellery cleaner liquid can be used. A professional jewellery cloth can be used to give your jewellery a quick polish and shine. Periodic ultrasonic cleaning (at least once a year) by a reputable jeweller is recommended to clean hard-to-reach areas. Depending on the nature, nicks and scratches can be removed through polishing by a reputable jeweller.
    All jewellery should be stored individually to prevent scratching. Chains, bracelets and other jewellery less flexible than jewellery with links, should be stored flat on an even surface.
    It is not an easy task to repair semi-hollow jewellery. Avoid disappointment by buying more solid pieces.