This isn't about naturally rare minerals, it's about the one mineral that's rare by design. This is the latest in a long history of disinformation campaigns intended to keep DeBeers' control of the diamond. In fact, diamonds are so common in nature that there are beaches in Africa where they wash up on shore. You could pick them up like seashells if it weren't for the armed guards ready and willing to shoot anyone who tries. If DeBeers ever lost control of the market the value of diamonds would plumet.
When General Electric developed the first artificial diamond DeBeers bought the company. When Israel threatened to dump their cache on the market, DeBeers practically bought the country. They spent billions buying artificial diamonds from the Soviets, just to keep them off the market. In the US, when DeBeers was investigated for antitrust violations they put every employee in their country on a plane and sent them back to Europe. In one night. The next day there was a new person in every US job, and not one of those people could testify about how DeBeers operates. If you ever want to have your life turned upside down, try buying and selling used diamonds. See just how long it takes for DeBeers to shut you down.
DeBeers modus operandi is to back whoever controls a country, as long as they are willing to do business. If not, DeBeers will back a coup. So, if you want to control an African country, step 1 is to gain control over the diamonds. If you want to get rich, step 1 is to take over a country. THAT is why there's so much violence in Africa. The regime that labels "conflict" minerals is just one of the tools DeBeers uses to maintain control. The "conflict" countries are places where more than one group operates. Whatever group is on the outside will smuggle diamonds out, undermining price controls.
The history of the DeBeers cartel is the most fascinating and disturbing story that's rarely told. If you haven't read it I strongly recommend a trip to the local library. Don't wait for Hollywood to tell the story. They're too busy writing a sequel to "Blood Diamonds". On contract of course. The sad truth is that EVERY diamond is a blood diamond.