Where does the word "tempering" come from?

An Australian smelting company has set up a branch in China, mainly engaged in smelting raw materials, technical consultation and electrolytic copper trade. This company needs to recruit people who know the market situation in China.

Of course, there are many applicants and the competition is fierce. The four people who finally won the "three out of four" are experts in the metallurgical industry.

All four are determined to win. Most of them are engineers from several well-known smelters in China, who hold technical management positions in their original units and have rich experience.

The top three have successfully passed the test, waiting for the company's final decision. The last one is confident, too. He has a bachelor's degree and is an engineer in a smelter. Of these four people, he is the most qualified.

The examiner asked several questions in English and he answered them fluently. A smile appeared on the examiner's face.

Finally, the examiner took out two large plates from the drawer, which contained more than a dozen black stones of different sizes, and said, "Please pick out the matte and waste residue within one minute."

The difference between matte and waste residue is so subtle that people without years of practical experience can't tell it quickly.

He froze, and in desperation he just classified them by feeling.

The examiner looked at his classification and asked, "How did the matte and waste residue come about?" He said: "matte is an incomplete product of high-temperature smelting process, and the grade of copper can reach more than 70%." It needs to be reheated to produce crude copper with a content of more than 97%, and the waste residue is the result of completely high-temperature smelting. The copper content is only about 1%, and the rest is calcium carbonate and iron. "

The examiner took the plate containing waste residue, took out all the matte that he had misclassified, and said to him, "These are semi-finished products, and they should be reheated."

He bowed his head in shame and said to the examiner, "Sorry, I have been engaged in technical management all the year round, and I have too little time to go to the production site."

He was not hired, because for that company, a technician who can't tell matte from slag is inconceivable.

Later, he went to ask a smelting technician in his unit how to distinguish matte from slag in the simplest and quickest way. The technician told him: "You can look at the color, look at the appearance, or feel it." He is puzzled by the way of distinguishing by touching. The technician explained, "Copper is more important than stone."

This basic common sense is also a good way to deal with it, but he didn't think of it. He is like a piece of high-grade matte. Although it is more expensive than waste residue, it needs to be calcined again.

Life experience: Some people are like a piece of high-grade matte. Although it is higher than waste residue, it needs to be re-calcined.