The trading mechanism is similar, but the disk sticking phenomenon of precious metals, gold and silver is more serious. Various mechanisms for oil trading are more perfect. Moreover, oil investment is supported by the state, and the internal market is safer and more reliable. A few of my friends used to make gold and silver, and they all lost money, so it was difficult to do it. Oil emerged in 20 14. There is still a great chance to do it now, but it will be bad to enter the market in the future.