The second is the accelerating collapse of natural diamond markets in the face of increasingly cheaper laboratory-grown gems and wider consumer trends. To wit, Anglo agreed in May to sell its steel-making coal business in Australia to privately held, UK-registered mining group Dhilmar for up to $3.785-billion. The bottom line is that Anglo has been able to exit its steel-­making coal business without offering it at a bargain. And Botswana’s “economic miracle” and coveted investment-grade credit rating are threatened by the unfolding collapse of the natural diamond industry. And a natural diamond forged from billions of years of geology has hit its sell-by date.