The Chinese historian Sima Qian, writing a century after the First Emperor's death, wrote that it took 700,000 men to construct the emperor's mausoleum. British historian John Man points out that this figure is larger than the population of any city in the world at that time and he calculates that the foundations could have been built by 16,000 men in two years. While Sima Qian never mentioned the terracotta army, the statues were discovered by a group of farmers digging wells on 29 March 1974. The soldiers were created with a series of mix-and-match clay molds and then further individualized by the artists' hand. Han Purple was also used on some of the warriors.