The complex story behind Lesotho's promise. This rough diamond weighing 613 carats was discovered in the Lesotho Mountain Kingdom and may be the most anticipated diamond of the 21st century. Watch a world-class professional team pursuing perfection create history. From the mines where it was unearthed to the headquarters of Graf Diamond Company, which transports polished stones, here you can find a rare opportunity to glimpse how this important stone became a gemstone. Written by Yves Alexis