It may be fake. You can use sensory inspection when you buy it. Look at the color, pure gold is dark yellow, K gold has yellow, red, white and other colors, while imitation gold products are mostly copper alloys with lighter colors. In terms of weight, the proportion of gold is much higher than that of imitation gold products. For example, a gold ring weighs about 5 grams, while imitation gold products of the same size generally weigh less than 3 grams. Hardness test shows that pure gold is soft, scratches will appear when scraped with a pin, and tooth marks will appear when bitten with teeth.