1. Check the seal Now all the gold ornaments produced by China manufacturers have the words "our seal" and "gold content".
2. The density of weighted gold is higher than that of silver, copper, lead, aluminum and other metals. The same volume of gold is 40% heavier than silver, 1.2 times heavier than copper and 6. 1 times heavier than aluminum. When gold is in your hand, you will feel heavy.
3. Look at the color. Generally, the higher the purity of gold jewelry, the darker the color. Pure gold is yellow purple, 18K is yellow blue, and 14K is yellow red.
4. Listen to the rhyme and throw the gold jewelry on the hard ground. Listen when you land. The sound of real gold is deep and heavy, and there is no lingering sound. The sound of fake gold is crisp and not dull, generally it is a "Dangdang" sound, and the sound is lingering. Real gold didn't jump so hard when it landed.
5. Testing hardness Pure gold has a small hardness and can be bent by hand. Fake gold feels hard when it is bent by hand. If you scratch jewelry with a pin, the scratches of pure gold products will be clearer. Jewelry with low gold content is vague even if it can draw traces. Gold-plated jewelry is more blurred. The above methods are simple test methods.
In order to accurately identify, the following three methods can be used. 1. Burn the jewelry in the fire and take it out when it turns red. After cooling, the color of pure gold jewelry is still as new, and the surface of K gold jewelry presents a smoky gray oxide layer. The lower the purity, the darker the color.
2. Touchstone Method Select a black touchstone with delicate texture, and mark the touchstone with gold pieces with different gold contents as a comparison standard. Then scratch the jewelry to be tested on the same touchstone, and drop concentrated nitric acid to remove impurities. The trace left on the touchstone is the gold content of jewelry. According to the standard, find out the same chromaticity as the trace, that is, the accurate gold content of the measured jewelry.
3. Chemical method drops 70% nitric acid on jewelry respectively, and the real gold is the first one to remain unchanged. It's not real gold jewelry that reacts chemically.