In the case of gold jewelry, various markings are used to determine quality and purity, which are used to guide the purchaser through the seal of the quality control institute.
The purest gold, the fine gold, is only 999.9% pure since it always contains all the impurities. As the pure 24 carat gold is too soft, it is blended with other metals to make it suitable for jewelry making.
The most common stamps are: 22kt 91.67%; 18kt 75.0%; 14k 58.33%; 10ct 41.66%. That is, in 10 grams of 14 carat gold jewelry, 5.83g of gold is gold and 4.17g of other alloying metals (such as silver, copper, nickel, zinc, indium, gallium - the proportion depends on the color we want).
Nickel is often used in the production of white gold, but because it is a highly toxic substance, the amount of alloy in white gold rings and jewelry is regulated separately in the European Union. Palladium is still a substitute for nickel, but we have to pay more for this alloy.
The price of a gold jewelry is not only determined by its purity: the weight of the jewelry is just as important as the design, the gemstone decoration, or the special socket.