China itself is has one of the world's top oil reserves. Just about 30% less than the US.  If decoupled, it can trade with Iran and restart oil production in Venezuela.  Venezuela has the world's largest reserves. Larger than Saudi Arabia.  Both Venezuela and Iran combined have 30% of the world's oil reserves.

China has the third largest reserves in iron after Australia and Brazil.

4th in coal. 3rd in copper production. 1st in rare earth. 6th in gold. 2nd in silver. 9th in Nickel, ...

No. 1 in production of Aluminum, Titanium, Tin and Zinc.

So the myth of a resource hungry China is just a myth.  It may be so during the rapid expansion in the 90s and early 2000s as demand outstrip production capabilities.  That's why stupid Australia who is still stuck in the "Whites Australia" era thing it can play hardball with China based on this myth.  China can just walk away after helping Australia sustain a two decade unprecedented growth.