Swathed in vibrant woollen blankets against the biting winter chill, jockeys - some no more than boys - thundered down a dusty track carved between the undulating hills of the tiny kingdom of Lesotho.

Letšeng Diamonds is jointly owned by Gem Diamonds Limited and the government of Lesotho. It is widely regarded as one of the country's most strategic economic assets. The mine is a key contributor to ...