Gold Alloys used for Jewellery
As a general rule, gold metal is very strong and does not rust, corrode, or tarnish. Despite its strength, it is the most malleable of all precious metals 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.
Caring for platinum is similar to any other precious metal. If your platinum jewellery becomes scratched, it can be brought in for polishing.
White Gold
Rose Gold
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.
***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.
