08/11/2024

All you need to know about gold jewellery

Gold jewellery, synonymous with luxury and elegance, has played a central role in civilisations throughout the ages. Worn for their beauty, durability and symbolic significance, gold jewellery is much more than an accessory: it embodies cultural values, investments and personal memories. But beyond their historical value, gold today comes in a diversity of colours and purities that make it more accessible and suited to contemporary tastes.
All you need to know about gold jewellery
The colours of gold: a diverse palette of shades and alloys

While yellow gold remains the most emblematic colour, it is now available in a variety of hues. This change in colour is made possible by a process called alloying - the mixing of pure gold (24 carats) with other metals. This not only makes the gold more robust, but also allows different shades to be obtained.
  • White gold: This alloy is created by combining pure gold with white metals such as palladium or silver, then often coated with rhodium for a shiny, hard-wearing finish. White gold is now the preferred choice for wedding rings in the United States.
  • Pink gold: The pink hue comes from the addition of copper to the gold, giving the alloy a soft, warm colour.
  • Less common colours: Shades such as blue and violet are created by adding patinas or oxides to the surface of the alloy, while black gold derives its colour from cobalt oxide.
 
Gold caratage: a measure of purity

The weight of gold is measured in troy ounces (1 troy ounce = 31.10 grams), while its purity is expressed in carats.
Caratage indicates the percentage of gold in an alloy:

  • 24 carats: pure gold (99.9% gold)
  • 18 carats: 75% gold, with 25% other metals (often copper or silver)
The minimum carat for an object to be considered gold varies from country to country. In the United States, the minimum legal standard is 10 carats (41.7% gold). In France, the UK, Austria, Portugal and Ireland, the minimum purity of gold is 9 carats or 375. In Denmark, Germany and Greece, it is even lower, at 8 carats or 333 thousandths fine.

Finesse: Another measure of purity

The purity of gold can also be expressed in parts per thousand, known as fineness. Here are the corresponding values:
  •  **375** = 9 carats
  • **417** = 10 carats
  • **585** = 14 carats
  • **750** = 18 carats
  • **999** = 24 carats (pure gold)

In theory, 14-carat gold should have a fineness of 583 (14/24 = 0.583), but most manufacturers follow European practice and increase this purity slightly, thus marking 14-carat gold with a fineness of 585. Similarly, 24-carat gold, although ideally 1.0 (24/24 = 1.00), generally contains slight impurities, reaching a fineness of 0.999.

Accepted purity tolerances vary from market to market. In China, for example, gold called Chuk Kam (meaning ‘pure gold’ or ‘full gold’) accounts for the majority of sales and must contain a minimum of 99.0% gold, with a negative tolerance of 1.0%.
 
Composition table of alloys by colour and caratage



In conclusion

Gold, with its different colours and levels of purity, offers jewellery lovers a multitude of choices. By mastering alloying techniques, jewellers are able to transform this precious metal into works of art in a variety of colours, to suit individual tastes and exacting quality standards. Whether you prefer classic yellow gold, dazzling white or warm pink, each shade carries the heritage of expertise and the promise of timeless value.
News See all
Here you will find important information on economic and financial news as well as information that may have an impact on your investments in gold or foreign currencies
All you need to know about gold jewellery
2024-11-08

All you need to know about gold jewellery

Gold jewellery, synonymous with luxury and elegance, has played a central role in civilisations throughout the ages. Worn for their beauty, durability and symbolic...
Gold hits all-time highs
2024-11-07

Gold hits all-time highs

Gold closed the month of October at €2520/ounce for a monthly gain of 6.5%, continuing its string of all-time highs. Since the start of 2024, the yellow metal is up 35% at...
Australian Lunar Gold Coins: a numismatic work of art
2024-11-07

Australian Lunar Gold Coins: a numismatic work of art

The Lunar Series of gold coins minted by the Perth Mint represent a unique combination of culture, art and first-class investment. Since their launch in 1996, these coins...
Understanding the Exter Pyramid and its use in global finance
2024-10-10

Understanding the Exter Pyramid and its use in global...

The Exter pyramid was conceived in the 1960s by John Exter, a former economist at the US Federal Reserve, at a time when economic crises were becoming recurrent. Having...