The purity of gold refers to the content of gold. Generally, K is used to indicate the purity of gold. 24K gold has the highest purity, followed by 18K and so on. The name of gold depends on its purity.
18K gold means that the gold content is 18/24, that is, 75%, and the remaining 25% is other metals, usually copper and silver in gold ornaments. 24K gold means pure gold. Relatively speaking, consumers in China have higher requirements for the purity of gold ornaments, so in the China market, the more common gold ornaments are 24K and 18K.
In Europe and America, people have a greater demand for the beauty of gold ornaments. We can see many low-purity gold ornaments, such as 12K gold and 14K gold. These purities mean that the gold content is 50% and 58.33%.
Extended data
Content naming
The name of gold depends on its purity. For example, gold with a purity of 99% is called "pure gold", gold with a purity of 99.9% is called "thousands of gold" and gold with a purity of 99.99% is called "ten thousand gold" or "high pure gold".
There is an idiom called "gold is not full of red, and no one is perfect". In fact, 100% pure gold does not exist.
One reason is refining technology, and the other reason is that gold ornaments or gold bars are in the process of processing.
According to the Regulation and Naming Method of Precious Metal Purity of Jewelry (national standard GB/T1KLOC-0/887—2002), the minimum purity of pure gold is 990, that is, the purity is not less than 990 ‰; The minimum purity of thousands of gold is 999, that is, the purity is not less than 999‰.
In the standard here, the purity range of precious metals in precious metal jewelry does not include flux components, but the content of finished products shall not be lower than the specified purity range. The national standard on the purity of gold refers to the minimum purity. However, the purity of most pure gold and thousands of pure gold raw materials in the domestic market exceeds this minimum (the purity of pure gold reaches 995‰ and the purity of thousands of pure gold reaches 999.5‰).
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