"which will grow when the world economy grows"
It looks like to me that peak CONVENTIONAL crude oil occurred in 2004, while working age labor demographic has also peaked in all nations that matter, so growth seems over to me. This is also one reason the whole debt based system is collapsing. It needs infinite growth to not implode when the interest due is always greater than the principal, making deflation or even equilibrium a death sentence.
The only area with any real working age demographic growth is Africa, but they already can't feed themselves, so it's unsustainable r-selection growth that will just end in famine and plague.
Platinum to me, I want to like it, but it's difficult. For one thing, they're phasing out platinum in things like hydrogen fuel cells. Then when the whole debt based system goes bust, several of these enormous car manufacturers will probably go bankrupt and have thousands of vehicles sitting in lots to dispose of where they'll dump the catalyst platinum en masse.
For the near term over the next five years, I think gold and silver will probably perform better as monetary metals and defy the usual platinum relationships in charts even though platinum cost of production dwarfs both. That is, unless there's a large war and then platinum would probably be high in demand, but govt wouldn't allow you to trade it.
I'm mostly focused on betting against the US debt, profiting from monetary reset, US debt default, etc. I consider 1971 as a US debt default, so it's not an uncommon occurrence. I just don't really see platinum playing a huge role in all that and think the lottery tickets are silver, gold, and bitcoin.
If you're sitting on like $100,000+ in liquid money, by all means buy like an ounce or two of the stuff just for the hell of it since the price for it is good right now, and in case some random fool pumps it like palladium did, but otherwise I don't expect a new Bretton Woods for platinum.