A century ago crude oil was the most valuable substance on the planet, but the coronavirus pandemic has caused the price per barrel to plummet. But how have the likes of diamonds, gold, and platinum fared? Plus there are a host of other obscure materials you’ve probably never heard of that command a high price for the fact they’re ultra-rare, hard to extract or valued for highly unique properties. Click or scroll through to discover the most valuable substances on Earth, as of their prices at the time of writing (22 March).