Gold’s chemical symbol is Au. It comes from the Latin word aurum which means shining dawn, a reference to its bright yellow colour and shiny luster. Alloys (mixtures) of gold and other base metals are extensively used in jewellery and electronics to reduce the amount of gold used while assuring the positive features for which gold is desired.
THE KARAT OF GOLD
Karat is the measure of gold content. The Karat measures the proportion of pure gold mixed with other metal alloy to make up the final metal. The Karat of gold is denoted by the abbreviation Kt or K. Please note that carat or ct is used to measure the weight of diamonds and gemstones.
The higher the percentage of gold used in the final metal, the more valuable and expensive the metal will be. So all other things being the same, an 18K ring will be more expensive than a 14K ring and a 14K ring will be more expensive than a 9K ring.
9Karat gold contains 37.5% of pure gold. 9K is popularily used in UK to make jewellery to minimize the cost. The hallmark stamp for 9k gold is 375.
14Karat gold contains 58.5% of pure gold. The jewellery made with 14k gold comes stamped with 585.
18Karat gold contains 75.0% of pure gold. 18K is highly used in gem and diamond set jewellery. The hallmark stamp for 18k gold is 750.
22Karat gold denotes 91.8% gold purity. Gold in 22K is very soft and is not suitable for making stone set jewellery. It is used for making plain gold jewellery.
24Karat gold stands for pure gold. Gold in this form is extremely soft and cannot be used for any type of Jewellery making.
White gold is made from yellow gold by mixing it with other metals like palladium and silver. White gold in purity commonly comes as 9Karat, 14Karat or 18karat. 18Karat is the purest form of white gold. It is the most popular metal used in engagement rings and wedding bands. Please note that hallmark stamp for white gold is same as yellow gold. So 9Karat white gold is stamped 375, same as 9Karat yellow gold.
The final colour achieved by mixing the above metals to make white gold is slightly off white, with yellowish tint (as it is made from gold). To make it completely white, all white gold jewellery is plated with a metal called Rhodium. Rhodium is a very white shiny metal and is used on all white gold jewellery. Gradually this plating comes off, when one can see the original colour of white gold. How quickly it comes off, depends on the weareR. However when rhodium comes off, the piece of jewellery can be re-polished and rhodium plated.
GOLD IN EVERYDAY WEAR
It is highly recommended not to wear any sort of jewellery during heavy manual work or when handling harsh chemicals. The gold jewellery should be stored in such a way that it doesn’t get scratched from other pieces.
Diamond or any stone setting should be periodically checked for any damage to the gold prongs/claws or bezels. If you find the stone is loose or any of the claws is damaged, immediately stop wearing it and take it to a professional jeweller for repair at once.