The only way a cartel can work is via government enforcement. Cartels can try to fix prices, but as soon as they do, if the price is above the free-market pric

The only way a cartel can work is via government enforcement. Cartels can try to fix prices, but as soon as they do, if the price is above the free-market price, members of the cartel will try to gain marketshare by selling under the table at a lower price. Cartels are not sustainable in a free market for this reason. I can't comment on DeBeers because I do not know enough of the history of the situation. I will say, though, that diamonds are essentially worthless, and it is primarily by brilliant propaganda / advertising that people continue to buy them.