Gold in jewelry: the notion of carat, history and practice
Sellers are sometimes disappointed when we tell them that their jewel is not made of 100% gold. Yet this has been the norm for as long as jewelry has existed… or almost.
From pure gold to the notion of carat
In ancient Egypt, among some Maya civilizations and even in Eastern Europe, archaeologists have found jewelry made of almost pure gold. While the luster is the same, the color is noticeably yellower and, above all, the jewels are very often misshapen.
They are ceremonial jewels, or jewels made on the death of an important figure of the time (the pharaohs in Egypt, for example): pectoral necklaces, cuff bracelets, or rings set with hardstone intaglios engraved with symbolic animals such as the scarab.
When worn, these jewels inevitably lost their shape. Gold is a soft, malleable metal; in its purest form, it withstands knocks poorly.
Goldsmiths of the time therefore had the idea of mixing gold with other metals, such as silver or copper, to create alloys. Today, the proportion of gold in a jewel is expressed in carats. The purest gold is 24-carat gold, or 1000/1000.
Ancient jewelry and the arrival of 22 carats
Greeks and Romans adorned themselves with jewelry to display their power and wealth. They favored 22-carat gold (917/1000). Intaglios and cameos were the privilege of the wealthiest men, and the skill of the engravers of the time was remarkable given the tools at their disposal.
Some countries still favor 22-carat gold today, such as India, Sri Lanka and the Gulf states. It is used there by tradition and for its very subtle patina, a highly characteristic canary yellow.
Note also that most British gold coins are 22-carat gold, while French gold coins are 900/1000.
18 carats, the classic gold of fine jewelry
From the 18th century with the farmers-general, and above all in the 19th century with the famous eagle's head hallmark, 18-carat gold, or 750/1000, became the standard for fine jewelry. Most of the jewelry you wear is therefore three-quarters gold. This produces a jewel that does not lose its shape, or only slightly. Gold can also take on several colors depending on the alloy: rose gold is richer in copper, while white gold contains palladium.
14 and 9 carats
Today, with the price of gold ever higher, jewelers tend to reduce the amount of gold in their jewelry. More and more jewelry is therefore made in 14-carat (585/1000) or 9-carat (375/1000) gold. This reduces the cost of raw materials while still allowing the jewelry to be described as made of the precious metal.
In summary: the French hallmarking table
