coal and diamond

It's probably some sort of magical or fictional ability. Maybe there's a special tool or power that enables him to do it.

Open pit coal mines should use mine safety certification. The coal safety certification was applicable to underground coal mines, while the mine safety certification was applicable to other metal or non-metal mines that were not coal mines. The open-pit coal mine belonged to the category of non-coal mines, so the mine safety certification should be used. If you want to know more about the follow-up, click on the link and read it!

The coal miners, often treated like slaves by the so - called coal kings, faced extremely harsh conditions. They worked long hours in dangerous mines with little pay. For example, they had to endure the constant threat of cave - ins and toxic gases. Their living quarters were usually shabby and overcrowded, and they had few rights or protections.

According to the degree of coalification, coal could be divided into three categories: brown coal, bituminite, and coal. Hard coal was a general term for bituminite and anthracite. Among them, brown coal was the mineral coal with the lowest degree of coalification. Its ash value was generally between 20% - 30%. It was rich in volatile components, easy to burn and smoke, and the combustion would produce more ash floating in the air. Bituminous coal has a moderate degree of coalification, with a carbon content of 80% - 90%, a hydrogen content of 4% - 6%, and an oxygen content of 10% - 15%. It is relatively black in color, and the dyed hand is black. It is dense and brittle, and the stripes are black. When it burns, it emits thick smoke. According to the volatile content, the thickness of the colloid layer, or the technological properties, it could also be divided into long flame coal, gas coal, fat coal, coke coal, lean coal, and lean coal. The coal with the highest degree of coalification had a high fixed carbon content, the least impurities, low volatile components, and a high ignition point. It was not easy to burn on fire, and the burning flame was not obvious or even non-existent. From the point of view of usage, it could also be divided into thermal coal and so on. The thermal coal was mainly used to generate energy for heating or to drive mechanical movements and then convert it into other energy. In addition, China's coal could be divided into 17 sub-categories, namely, smokeless coal, lean coal, poor-lean coal, lean coal, coke coal, fat coal, 1/3 coke coal, gas-fat coal, gas coal, 1/2 medium-sticky coal, weakly sticky coal, non-sticky coal, long-flame coal, brown coal, etc.

Judging which type of coal was the "best" depended on a variety of factors, such as its use, coal quality characteristics, and so on. From the perspective of the degree of coalification, the coal with the highest degree of coalification had a high fixed carbon content, the lowest impurity content, and low volatile components. In terms of application, the smokeless coal could be used in fertilizer (nitrogen fertilizer, synthetic nitrogen), ceramic, manufacturing and forging industries; the pulverized coal could be used in the smelting industry, and could also be used for the filtering and purification of domestic and industrial water supply. From the perspective of burning to generate energy for heating or driving mechanical movement (thermal coal use), the coal with the lowest economic cost would be selected as the "best" choice. Although every type of coal could be burned, factors such as cost and combustion efficiency had to be considered. Bituminous coal could be divided into many types according to the volatile content, the thickness of the colloid layer, or the technological properties. It was a medium-level coal with a carbon content of 80% - 90%, a hydrogen content of 4% - 6%, and an oxygen content of 10% - 15%. It was mainly used as boiler fuel and raw materials for coke making. It could also be used to make gas and coal oil. Lignite was the mineral coal with the lowest degree of coalification. It was rich in volatile components and easy to burn and smoke. Burning it would produce more ash, but it could become an important chemical raw material after processing. Therefore, there was no absolute "best" coal, but the most suitable coal was judged according to specific needs and conditions.