Second, how to distinguish K gold jewelry from pure gold jewelry. The main specific hardness and elasticity that distinguish K gold from pure gold. K gold is harder than pure gold. Pure gold is purer and softer, and the mark can be bitten out with teeth, but K gold is not. K gold ring fell to the ground, which has a strong rebound, while foot gold ring fell to the ground, which has no such effect.
Third, how to distinguish gold-plated jewelry from real gold jewelry. Jewelry made of brass is plated with a thin layer of gold, which is of low value, because it is difficult to pass off as pure gold, but some people sell 18K gold, and the imprint of jewelry is marked with "18KGP". The appearance color of this kind of gold-plated jewelry is different from real gold, which is obviously reddish and lacks gold, and the appearance can also be distinguished.
Fourth, how to distinguish between nickel jewelry and platinum jewelry. Metallic nickel is the material for making one-dollar coins, which is white and does not oxidize, and looks like the color of platinum, but the specific gravity of platinum is 2 1.4g/cm3, while the specific gravity of nickel is only 8.85g/cm3, so the sense of thickness is obviously different.
5. How to distinguish silver jewelry from platinum jewelry? Although silver and platinum are similar in color, they are also easy to distinguish. The specific gravity of silver is 10.5g/cm3, which is only 1/2 of platinum. In addition, pure silver is soft and easy to oxidize, and will turn black after being placed in the air for a period of time, while platinum is different, harder and will not change color.