Since ancient times, gold has been considered the most valuable precious metal, but where does gold come from? A new study in the UK shows that the gold that people have extracted on the surface is brought about by a meteor shower more than 4 billion years ago. According to the current theory, in the initial stage of the formation of the earth, the molten iron gradually sinks toward the center of the spherical core, thereby forming a core. In this process, the vast majority of precious metals are also brought into the core, and the precious metal content in the surface should be extremely rare, far below today's production. So why now can humans “snap†so much gold on the surface? Some researchers have speculated that shortly after the formation of the Earth, there was a large-scale meteorite "bombing" the earth. The meteor shower formed brought a lot of precious metals to the earth, forming a geological thin layer containing precious metals on the surface. Geological activities have gradually become precious metal deposits. Researchers at institutions such as the University of Bristol in the United Kingdom analyzed ancient rocks from Greenland and supported the idea that "the sky is gold." The rocks they sampled were about 4 billion years old, and they benefited from the formation of the Earth's core and the period before the meteorite bombing. The researchers analyzed the characteristics of tungsten isotopes in these rocks, and analyzed the rock samples after the "bombing" of meteorites, comparing the two rocks before and after. They concluded that the "bombing" of meteorites did change the metal composition of the surface rocks. It is estimated that to produce the amount of precious metals found on the current surface, the "bombing" of the Earth's meteorites may reach 200 billion tons. zhejiang leima shoes ind.co.,ltd , https://www.safetyshoeschina.com