The word "carat" comes from the Arabic qīrāṭ, meaning "carob bean, small weight," which in turn was derived from the Greek kerátion 'carob', whose seed was used as a small weight.
One of the first things I learned while working at the Vicenza Jewellery Show was the classification of products based on their fineness and manufacturing techniques.
What is gold fineness?
In general, the fineness of a precious metal represents the ratio of the primary metal to any additives or impurities, thus establishing the degree of purity of the artifact (titolo in Italian and ley in Spanish). 100% pure gold is a very soft metal, so, besides the fact that an object in pure gold would have prohibitive costs, the risk of being damaged or deformed would be very high. This is why almost all gold artifacts (coins, jewelry, etc.) are actually made of gold mixed with another - more or less precious - metal. The most commonly added metals are copper, which conveys durability, and silver, which brightens up the color, hence the term alloy (lega // aleación).
Fineness is expressed in parts per thousand and it indicates the percentage of pure metal, in our case gold, present in the alloy. The number usually found inside the ring or on necklace and earring locks is the hallmark indicating the purity. For example, if you find "750", it means that the jewel is composed of 750 parts of gold out of 1000.
Fineness or carats?
Another way to express the purity of gold is the 24 karat-based system, in which 18/24 corresponds to 75% and therefore to a fineness of 750. This method is very ancient, dating back to a proportion system used by the ancient Romans, where the siliqua, a silver coin, corresponded to 1/24 of a solidus, a gold coin introduced by Constantine in the 4th century.
The second system is now preferred by English-speaking countries such as the United Kingdom and the United States, while in many European countries, including Italy, it is very common to find the hallmark with the gold title in millesimal finenesses.
Carats or karats?
The word carat derives from the Arabic qīrāṭ meaning ‘carob bean, small weight’ which in turn derives from the Greek kerátion ‘carob’, whose seed was used indeed as a small weight.
Why do we speak about carats also for diamonds? What's the difference from those indicating the fineness of a jewel?
If in Italian the difference is not visible, in American English and Spanish the spelling is also different:
on one side, karat/K and kilataje/K refer to the gold fineness, on the other, carat/CT and quilatage/Q indicate the weight of the diamond, which is equals to 0.20 grams.
In fact, the carat is one of the famous Four C's, namely the parameters used to determine the value of the diamond: carat weight, cut grade, color grade, and clarity grade.
Note: In British English, the term ‘carat’ is used interchangebly for gold and diamonds.
When I work at the gold trade show as a business interpreter, one of the first questions that clients ask when they arrive to the stand is "How much does it cost?" followed promptly by "In how many karats?" because naturally the price of a piece of jewelry depends first of all on the karats, and therefore on the percentage of gold in that alloy. In Italy, jewelry stores usually sell 18-carat products, but the preferred gold fineness varies depending on the country. The most common alternatives are 14 k, 9 k and more rarely 10 or 19 k.
Not all that glitters is gold...
Fine fold jewels (oro massiccio // oro de ley) are made by an alloy of metals, of which pure gold is only one of the elements, unlike those jewels made by a less noble metal which are then covered by a more or less thick layer of gold.
The latter, despite seeming golden, have a minimal percentage of gold compared to the main metal they are made of. This is the case, for example, of gold filled jewelry (oro riempito // oro relleno). In Italian, another term used for this kind of jewels is ‘oro antico’, which means ‘ancient gold’. Despite its name, ‘ancient’ does not refer to the age of the jewelry but to the type of processing. In fact, gold-filled ‘ancient’ jewelry dates back to the Victorian era when the demand was high and so was its popularity also due to the scarcity of gold. If treated with care, gold-filled jewels can last for decades, precisely because the gold sleeve is much thicker compared to plated jewelry, but the cost is lower than jewels made with a gold alloy.
Gold-filled and gold-plated jewels are entirely different things: the former refers to jewelry with a copper base covered by a layer of solid gold representing at least 5% of the item's total weihgt. Gold-plated jewelry, on the other hand, can have a base of copper or other less valuable metals and a layer of less than 2.5 microns, therefore very thin and with a much lower value.
As regards silver jewelry, the most precious and durable pieces have a fineness of 925: they are made of 92,5% silver, with the remainder being copper. Silver 925 is most commonly known as sterling silver. Sound familiar? That's likely because sterling is also the currency of the United Kingdom and its territories. The pound is the main unit of sterling and is internationally known as British pound or pound sterling.
Spain, on the other hand, chose to keep the same term used for fine gold (oro de ley) and adapt it to silver: plata de ley,
Always rely on a professional translator or interpreter to translate your website or to communicate with your clients at a trade show.
Remember that there are carats and karats: the devil is in the detail.
