pardon me, silly and ignorant questions coming....
1. What do we do with Diamonds besides turning them into jewellery?
2. What do we do with copper and nickel? I know they are mixed together (or they don't?) but what end product is made from these metals that is valuable?
3. What do we do with Platinum besides turning them into tennis racket and gold clubs?
4. and finally, regarding energy sector, what materials contribute to energy sector? The only one I know is gas.
thanks in advance.