Purification of mixed mercury and gold. This is an ancient gold purification method. As long as you are patient, you can improve your purity. The specific method is as follows:

Amalgamation: gold+mercury+water; Continue grinding until there are no gold particles, and gold and mercury form intermetallic compounds.

Sulfur addition: grinding and mixing sulfur powder and mercury homogeneous gold.

Heating and roasting in the air: at this time, excess mercury volatilizes, and the base metal forms metal sulfide and then metal oxide.

Repeat the above operation many times.

Adding borax to melt into gold ingot: base metal oxide reacts with borax to generate low melting point substance, which floats on the upper liquid and pure gold is at the bottom.

This method is used to prevent mercury vapor poisoning.

In ancient times, because there were no chemicals such as nitric acid and sulfuric acid, the above methods could only be used. Now we can improve the above method:

All amalgam

Nitric acid was added several times to remove impurities.

mix together

If handled properly, the purity of gold depends on the sufficiency of amalgam and the thoroughness of removing nitric acid impurities. The purity of gold can reach over 99%.

This method is suitable for the treatment of crude gold collected by mercury.

Extended data:

Gold is a simple form of chemical element gold (chemical element symbol Au), which is a soft, golden yellow and corrosion-resistant precious metal. Gold is a rarer, more precious and more valuable metal. Generally speaking, gold in the world is measured in ounces. In ancient China, gold was measured in ounces, which was a very important metal. It is not only a special currency for reserve and investment, but also an important material for jewelry industry, electronics industry, modern communication and aerospace industry.

The chemical symbol of gold is Au, and the financial English code is XAU or gold. The name Au comes from a story of Aurora, the goddess of dawn in Roman mythology, which means shining dawn.

After the international gold price entered 20 15, it soared all the way. The gold price in new york market rose from $0/200 per ounce to $0/300 per ounce in less than a month. Statistics show that since 20 15, the price of gold futures in new york market has increased by 9.3%.

References:

Gold-Baidu Encyclopedia