High-purity gold refers to a gold product with a purity of 99.999%, which is called high-purity gold and marked as AU99999. High pure gold is purer, redder and purer than Wanjinjin AU9999.
The highest purity gold in the world reaches six nines, that is, 99.9999%, but it is generally used as reagent gold. Jewelry gold does not need to use high pure gold, but generally uses pure gold and thousands of gold. Jewelry made of high pure gold is easier to deform and scratch.
Extended data
I. Inspection method
1, jewelry weight
The price of gold jewelry is calculated according to the weight and processing fee, and the weight of jewelry is one of the important indicators. According to the standard, the weight of jewelry is measured in grams, and the tolerance of a single piece of gold jewelry is 0.01g.
2. Gold content of currency
The gold content of jewelry is an important indicator of its quality. There are many methods to test gold content, which can be divided into chemical analysis and instrumental analysis. According to whether jewelry is damaged in the process of testing, it can be divided into nondestructive testing and destructive testing.
The daily inspection of jewelry quality supervision department is generally based on nondestructive testing, density method combined with X-ray fluorescence spectrum, electron probe and other large instruments. Damage detection is the main method of market supervision and spot check, and fire assay is the national detection method for determining the gold content of jewelry.
Second, related stories
More than 200 years BC, the Greek mathematician Archimedes worried about judging whether a crown was made of pure gold.
While taking a bath in the bathtub, he discovered Archimedes' law of specific gravity: an object immersed in a liquid is subjected to upward buoyancy, and the buoyancy is equal to the weight of the displaced liquid. Thereby successfully confirming whether the crown made by the king is made of pure gold.
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