999 refers to pure gold with a gold content of 99.9%. True blue will never stain. If you are not sure about the authenticity of 999 gold, you can barbecue on the fire. Nothing will change after the real gold is barbecued, and the color of the fake gold will turn black after the barbecue.

As a precious metal, gold has always occupied great value in the precious metal market, because it is not only the currency for investment and reserve. At the same time, it can also be forged into various ornaments and make high-tech products. So it makes sense to price gold in grams. In fact, our common 999 gold, commonly known as thousands of gold, is not pure gold.

Pure gold 999 is a gold product with a gold content of not less than 999, and there are other metals, which can't be regarded as pure gold. And because of the lack of modern technology, we can't extract gold products with gold content of 100%. Of course, even without pure gold, there are still many ways to verify gold. For example, gold will not turn black and disappear when heated at high temperature.

Identification of thousands of gold:

1, look at the color. The higher the purity of gold jewelry, the darker the color.

In the absence of comparing gold medals, the approximate fineness can be judged by the color of cyan gold, which only contains silver in gold.

The fineness of deep red yellow is above 95%, light red yellow is 90-95%, light yellow is 80-85%, blue yellow is 65-70%, blue white is only 50-60%, and yellow white is less than 50%.

2. look at the weight The specific gravity of gold is 19.32, which is heavier than silver, copper, lead, zinc, aluminum and other metals.

Because the volume of gold is more than 40% heavier than that of silver, 1.2 times heavier than that of copper and 6. 1 times heavier than that of aluminum. Gold ornaments should feel heavy in your hand. 18k gold pendant, fake gold ornaments feel light and floating.

3. Look at the hardness. Pure gold is soft and has low hardness. You can draw shallow marks with your nails and bite out teeth marks with your teeth. In Jindao, gold ornaments with high fineness are softer than those with low fineness, and the more copper they contain, the harder they are. Bending method can also be used to test hardness. Pure gold is soft and easy to bend, and the lower the purity, the more difficult it is to bend.