In fact, G750 is the same as 18k, but with two different names. Because the purity of gold is relatively high, the higher the purity, the softer the gold is, so gold cannot be inlaid with any gems. The composition of G750 is 75% gold, and then copper, iron, zinc, palladium, silver and other metals are added to make another 25%. The hardness of G750 made in this way is much higher than that of gold, and it can be made into any style and the price is cheap, so G750 is widely used in gem setting.