Identify gold through technological means

The identification of gold is very convenient through modern scientific and technological means, but for ordinary consumers, it can only be identified through folklore to see its fineness. In the past, people often used touchstones to determine the general content of gold. Touchstones are a kind of carbonaceous quartz and gold identification. It is very convenient through modern scientific and technological means, but for ordinary consumers, it can only be done through private The practice of the legend is to be identified and see the condition. In the past, people often used touchstones to determine the general content of gold. Touchstones are a mixture of black minerals containing carbonaceous quartz and opal. If you draw a stripe on the touchstone, you can see the general color of gold. Whether it is natural gold or finished gold products, its color will vary with the ingredients contained. Pure gold: shiny dark yellow, strong yellow; silver-containing gold: lighter in color, slightly greenish; gold with more than 25% silver: earthy white; copper-containing gold: darker in color and red tones; silver Copper gold: yellow; gold containing zinc, copper, and nickel: platinum. Only when there are comparisons will they be distinguished. The specific gravity of gold is 1 cubic centimeter and it weighs 19.3 grams, which is twice as heavy as copper (8.5 grams of brass). The contrast is clear. As long as you weigh the weight and compare it, it is self-explanatory. Real gold is not afraid of fire. Everyone knows the truth. Put gold jewelry in a big fire and burn it red. After cooling, if the surface is still golden, it is real gold; if it turns black, it is fake gold. The hardness of real gold is low, less than 3 (Mohs hardness is 0-10) biting lightly with teeth, it will leave tooth marks. The lower the color, the harder, on the contrary, the higher the color, the softer. Previous: Seven Methods of Identifying Gold Jewelry Next: Maintaining Gold from Two Angles