"True gold is not afraid of fire," saying that after the gold is burned, it is still golden and will not change color. In addition, real gold is not afraid of fire refining. It is also a good quality, and a strong-willed person can stand any test. After buying gold jewelry, many consumers choose to use fire to judge whether they are buying real gold. But can gold jewelry really be judged by fire? Gold jewelry is burnt black does not mean it is a fake In fact, this is also a way of not being a solution, but if the gold that has been burned by the fire becomes black, must it be determined to be fake? Not exactly that. Gold with a purity above the gold level will not turn black after being burnt, but blackening does not necessarily mean that it is a fake. First of all, gold has so many alloy products that it is normal to have insufficient purity and blackening. Besides, a piece of gold jewelry, especially a more delicate and complicated gold jewelry, there will be no solder joints. These solder joints will not be pure gold, so it is normal to appear black after being burnt. Gold jewelry identification method 1. Look at the color. According to the different luster and color of gold, it can be roughly distinguished from pure gold, K gold, real gold and fake gold. That is, gold is preferably reddish yellow (yellow red), the color is above 95%; the positive yellow color is about 80%; the blueish yellow color is about 70%; the yellowish grayish color is about 50%. Therefore, there are mouths for "seven greens, eight yellows, ninety-five red, yellow and white with gray and half gold." For long-time gold jewelry, there is a saying that "copper turns green, silver turns black, and gold never changes color." 2. 掂 weight. Gold is about twice as heavy as silver, lead and tin in the same volume. Real gold has a falling hand on the hand, while copper or other only has a heavy feeling without falling. 3. Listen to the sound. When the gold jewellery with high color is hit by a tap or throws hard, it emits a dull, low-pitched sound with no hum and no elasticity. K gold has phonology, sound, elasticity, and elasticity. The sharper the longer, the worse the color. The fake or low-quality gold sound is crisp and not dull, and generally gives a "dangdang" sound, and the sound has a residual sound. 4. Fold hardness. Gold with a high color can be traced with a pin or nail. More than 97% of the gold jewellery, after bending two or three times, wrinkles appear at the bend, also known as fish scales; 95% of the color of the gold jewelry, feels hard when bent, fish scales are not obvious; 90% of the color of gold Jewelry, hard when bent, no fish scales; gold jewelry with more impurities, bent two or three times to break; if it is made of raw gold, the bend is broken, the section has obvious sand-like shape. When using this method, the width and thickness of the jewellery should be considered. The thickness and width are harder, and the thinner and narrower are softer. 5. Identify the color with the touchstone. Use the gold that has been determined to be colored and the jewellery to be honed on the touchstone to determine the color of the gold jewellery by comparing the colors. This method should be carried out under natural light and fluorescent light, and not under direct sunlight and incandescent light. In the past, people used the touchstone to determine the general content of gold. The touchstone is a kind of mixed black mineral containing carbon and quartz and opal. The gold is marked on the touchstone and the general color of gold can be seen. Pure gold: bright yellowish yellow, thick yellow; silvery gold: light color becomes micro-spot green; silver containing more than 25% silver: earth white; gold with copper: darker color, reddish color; silver-containing copper Gold: yellow; gold with zinc, same, nickel: white gold. Boiled Wool Fabric,Boiled Wool,Boiled Wool Coating Fabric,Boiled Wool Knit Fabric Jiangyin Xiangxu Textile Co., Ltd. , https://www.xiangxutextile.com
Real gold is not afraid of fire? Can gold jewelry be fired to determine the true and false?