Manganese? Which exchange are you talking about? Is it Zhengzhou commodity exchange? I doubt foreigners can trade their products.
Investing in precious metals is a good idea. I'm confident that platinum, gold or silver have a good chance of bringing you small but steady profits. But before buying gold bars or silver coins, I advise you to clarify what the price of these metals depends on, what differences exist between gold bars and how to store your purchases correctly, and so on. Buying gold or platinum seems simple, but in fact there are many nuances that you need to know in order not to fall into a scam.
There is a battle going on between the two behemoths. Here's Grayscale's take on it... But it is a war with no substance. GC for the win.