The other part where the Global South/SCO is important to China is rare earth. China has the largest proven RE deposit in the world, but is jut a fraction of the overall world production. Russia, Vietnam and Brazil also have large production.
Although many countries can produce rare earths, China is where the all the rare earth metals go to get processed. Western countries have long complained about the need to rely on Chinese processing of rare earth metals. That includes the ones mined in Australia.
This was posted in the ASEAN economy thread. It's quite interesting and makes a lot of sense for Chinese firms to be doing. It is very similar to the mining they already do in Northern part of Myanmar.
It's unclear how much rare earth deposits are in these 2 countries, since there are no public figures, but sounds like Chinese companies will be actively working with local firms to mine and then doing advanced processing back in China. This ensures that Chinese rare processing industry remains in control of the this process and provide advantage to Chinese producers of magnets and over rare earths products.
It seems China has made similar in road into Africa where the metals are sent to China for processing
Aside from this, Mongolia is said to have a large rare earth reserve also. This makes sense since Inner Mongolia have large RE reserves
It's probably important for Chinese firms to work with Mongolian miners to make things as easy for them as possible so that the processing will continue to be done in China.
Finally, Russia, Vietnam and Brazil all have their own large deposits (although not as large as China). In each case, the country in question have not really ramped up their production of rare earth. They do not have a supply chain in place. As such, Chinese firms will need to work with them to ensure that processing is not being done by western companies. These countries may very well require processing to be done within their border. That I think is fine as long as Chinese firms are able to trade processing technology for continued supply.
What China wants is that these metals, which are important to renewable industries, continue to rely on the Chinese supply chain. And also that Wetstern companies don't develop anything close to a China free supply chain. That would require Chinese companies to continue to work with other countries and be involved in the mining, extracting and refining process. A whole that relies on Chinese rare earth supply chain is one that is dependent on China.