I had the idea to get some platinum exposure post-GFC as an inflation hedge. I picked an ASX-listed company with huge reserves in South Africa. I was right about the price of platinum going up (although, as your chart shows, it also came back down). I was wrong with my choice of company though. Mismanagement has caused loss of some mining rights and doubts over others such that almost 10 years later, the platinum is still in the ground and the share price languishing.

That said, I have recently started stacking and have added some platinum, and some rhodium and some ruthenium. More for kicks to have variety than anything. I probably would necessarily add more at the moment.