Find out the manufacturer and color by naked eye observation. The surface of regular brand gold jewelry should be marked with the manufacturer and alloy purity (fineness), and the text should be clear and delicate. If there is no mark on the jewelry, or the mark is rough and fuzzy, it is necessary to doubt the reliability of gold jewelry. Check colors and changes. Gold should be bright red and yellow with a lasting color. The higher the fineness, the more beautiful the color. On the other hand, if the color is not enough, as long as it contains 0.0 1% copper or silver, its color will be slightly purplish red or bluish white, so people often say "seven green, eight yellow, nine five red". The so-called gold jewelry is made of other metals and can be identified by its color. Auditory sound discrimination component. If jewelry falls naturally from a height, if it only makes a "beep" sound, and the tone is low and lacks elasticity, then the fineness of gold is high. If the sound is crisp and elastic, it means that the color is not high, and the jewelry contains more metal components such as copper. Hand balance method of comparing weights by hand. The easiest way is to weigh by hand. As the saying goes, gold "presses the hand" because the same volume of gold is much heavier than other metals such as copper. The specific gravity of gold is 19.3, which is higher than that of silver, copper, aluminum, tin and other metals. At the same volume, gold is 40% heavier than silver, 1.2 times heavier than copper and 6. 1 times heavier than aluminum. By comparing the weights, we can identify whether other metals are used to fake gold ornaments. Identification of real gold by bite mark method. Gold has low hardness and is relatively soft. If you bite with your teeth, there will be traces. Other metals do not have this characteristic. Moreover, the higher the fineness of gold jewelry, the softer it is, and the fineness can be checked by bending. If the color is low and contains more silver, copper and copper, it is not easy to bend. This method can be used to identify whether gold ornaments are shoddy or not. Licking your tongue can tell the truth from the false. Put the gold ornaments in your mouth and lick them with your tongue for a while, then smoke. If there is no smell, it is gold. If it is sweet, it means copper. As the saying goes, "fire and water are incompatible", but Jin is indifferent to fire and water. If possible, you can use the "fire and water solution" to see the true face of jewelry. Fire knows the truth. "Real gold is not afraid of fire" will make jewelry cool after high temperature fire. If it is still yellow and does not deform, it is yellow; If it turns black, it is a counterfeit product made of other metals. There is nitric acid to distinguish authenticity. Put jewelry in nitric acid, if it is gold, it will be safe and sound, and there will be no change; If it is copper, it will emit green smoke. In addition, some old gold ornaments in the past were often not very pure, and they were more or less doped with a little silver or even a little copper (sometimes the surface was green). You can put it in nitric acid diluted with water 1 time, heat it for half an hour, take it out and use less water. At this time, the silver and copper on its surface will be removed. If you add some salt to the nitric acid just now, if there is white precipitation immediately, it means that there is silver in the jewelry. Please rest assured that this treatment will not damage your gold jewelry, on the contrary, it will make the color of the jewelry more beautiful. Through the licking of eyes, ears, hands, teeth and tongue (which can be better than the high-quality bait known by others), plus the "fire and water method", the authenticity and quality of gold jewelry will basically be displayed to the world.