18K, also known as G750 gold, AU750, G 18K, where 750 represents gold content, AU and G are synonymous with gold, and 18K gold is a general term for 75% of 24K gold, so it is called 18K because/kloc-0. 18k = 18 * 4. 166% = 74.998%(750‰)。
The "k" of K-Gold is a foreign word "Karat", which is expressed as follows: Karat gold (K-Gold). The measurement method of K gold is pure gold 24k (that is, 100% gold content), and 24K gold is pure gold, but it is impossible to have 100% gold content in reality, so the content stipulated in China is 99.
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Advantages of 18K gold:
18K gold ornament not only has the precious value of gold, but also has the advantages of strong ductility, high hardness and changeable colors due to its perfect composition ratio. When used in jewelry design, it can give full play to the complex and exquisite creative expression.
18K gold has higher hardness and toughness than platinum. It can maintain stable performance in various environments, is not easy to wear and deform, and can give firm protection to diamonds, so it can be flexible in setting styles, and all kinds of complex and fashionable styles can also set diamonds well, so it is often used to match diamond setting.
Because it contains 25% other metals, 18K gold can also be made into different colors, such as white, yellow and rose red, which are called white 18K gold, 18K rose gold respectively. There are all kinds of colors, and western fashionistas wear unique and distinctive K-gold ornaments to highlight their personal style.