Gold Alloys used for Jewellery

Gold Bar 20gAs a general rule, gold metal does not rust, corrode, or tarnish and is very strong. Despite its strength, it is the most malleable of all precious metals when used for jewellery.

Purity

In its purest form is too soft to withstand every-day wear so in order to improve its durability and strength it is alloyed with a mixture of metals including copper, zinc, nickel, and silver.

    • 100% is equivalent to 24 Carat
    • 75% is equivalent to 18 Carat – stamped 750 or 18k or 18ct
    • 37.5% is equivalent to 9 Carat – stamped 375 or 9k or 9ct

Colour

Colour is determined by two factors- the percentage of each metal alloy mixed with it and the types of metal alloy used.

Yellow Gold

The purity used by Joseph George includes both 18ct and 9ct. 18ct contains a higher percentage of pure metal at 75% versus 37.5% in 9ct . The colour of 9ct is generally not as rich as that of 18ct because of the mixture with other alloys.

White Gold

Pure gold is mixed with different metal alloys to give it its white colour but it still has the same characteristics as yellow. It is mixed with metals such as nickel, palladium, zinc, and platinum rather than the copper and silver used in yellow gold. It is important not to confuse white gold with platinum; platinum is a much rarer and valuable metal than gold.

Most white gold is plated with rhodium in order to enhance the whiteness of the metal. Rhodium is an extremely hard metal which has a shiny, white look. Over time, it is possible for the rhodium to wear off. If this happens, re-plating can be done to restore the whiteness of your jewellery if needed.

White makes a beautiful setting for extremely white diamonds and when used in conjunction with yellow or rose, the effect is gorgeous. The purpose of white colour was to give a different look to jewellery and when used with yellow or rose, the piece is called two-tone.

Rose Gold

It has a beautiful pink colour which is achieved by using a larger amount of copper in the metal alloy.

Pricing

Jewellery pricing depends on a variety of factors including the metal type, karat weight, the design, and the construction.

Care

Gold jewellery should be kept from harsh chemicals such as chlorine and other cleaning fluids. The lustre of the metal is dependent on being spared from abrasive materials. Cleaning gold can be done easily with a mixture of warm water and a detergent-free soap. Always use a soft bristled brush when cleaning gold. When storing your jewellery, keep them in separate cloth bags or in their original boxes to protect them.

June 13, 2013