In order to improve consumers' awareness of self-protection, the Provincial Administration for Industry and Commerce issued consumer tips yesterday to teach consumers five skills in identifying gold and silver jewelry. First, how to distinguish gold jewelry from brass jewelry. Compared with brass, gold has a strong sense of heaviness and oppression in hand, because the specific gravity of gold is 19.32g/cm3, while brass is only 8.9g/cm3. The yellower the color of gold, the better the fineness. If it is reddish, it means that copper impurities are high. If it is white, the silver impurity is high and the gold color is low. 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 oxidize. The Provincial Administration for Industry and Commerce also reminded consumers to ask for invoices from merchants when buying any jewelry. The contents of the invoice should be more detailed and consistent with the jewelry you bought. If you buy jewelry inlaid with precious stones or diamonds, you should also ask the merchant for an appraisal certificate. Gold and silver are rare and precious metals. They have beautiful luster, soft texture and easy processing, so they become the most popular processing materials for craftsmen. Compared with other materials, this easy-to-process feature enables gold and silver vessels to be processed and transformed to form various forms of gold and silver products. For example, we can rework and transform the gold chain as before. To form necklaces, bracelets, rings, earrings and other essential accessories. On the other hand, due to the soft texture of gold and silver, its products are easily deformed or damaged after extrusion or collision. In addition, compared with other common metal materials, gold and silver have the characteristics of atmospheric oxidation and corrosion resistance, which can last for thousands of years and remain as bright as ever. Therefore, many gold and silver products have been handed down from generation to generation and become treasures handed down from generation to generation. Especially gold, this feature is better. It is not easy to lose luster. Compared with gold, this property of silver is slightly worse. Wet ozone will oxidize the surface of silver, which is what we see. When silver products are used or put on hold for a long time, their color will change from white to gray or black. In addition, silver is not as resistant to sulfide corrosion as gold. The identification of the authenticity of gold and silver vessels mainly includes two aspects, one is the identification of its material texture, and the other is the identification of its manufacturing age. For example, we can determine the fineness of silverware, the composition and content of other metals contained in silverware, and even the gold and silver content in different parts of a silverware. For example, the gold wares of the Warring States period unearthed from the tomb of Zeng Houyi in Hubei Province were determined to contain more than 85% gold and a small amount of silver and copper. Another example is the Ming Dynasty Jinbei unearthed in Shi Fo Township, Longyou County, Zhejiang Province. The gold content of the vamp is 73%, but the gold content of the foot and handle is only 60%. In addition, the feet are empty, so that the center of gravity will not be unstable after the gold cup is filled with liquid. Iron was added to the empty feet to balance the weight. Another example is the silverware unearthed from the Han tomb in Mancheng, Hebei Province. The content of silver is 66. 10%, copper is 27.8%, and tin and lead are 2.8% respectively. At that time, I had a deep understanding of silver-copper alloys. From my experience, I have also accumulated some simple and easy methods to identify the texture of gold and silver wares. (1) Generally speaking, the same volume of metal products, gold products are much heavier, and products that are too light must be fakes. (2) Gold and silver have low hardness, soft texture and strong ductility. If metal objects are used to understate gold and silver products, scratches are fakes. (3) The chemical properties of gold and silver are relatively stable, especially gold, which is not easily oxidized in air, while copper and iron products are easily oxidized and rusted. In acidic liquids (such as dilute hydrochloric acid and nitric acid). ), the color of gold remains the same, while copper products will lose their luster only when they come into contact with nitric acid. In the case of gold plating, the gold on the surface is easy to fall off, not only the falling part is easy to rust, but also the gold-plated surface is easy to rust by copper.