In 1964, the first atomic bomb developed by China was successfully tested, amidst the U.S.-Soviet Union oligopoly in nuclear weapon. A pit with a secret codename '111 Kuang' made significant contribution to the nuclear development. Today it is known as the Koktokay No. 3 pegmatite, located in Xinjiang. During the historical turning points and accompanying changes in Sino-Soviet relations, Koktokay, China's first non-ferrous industrial town, witnessed the pay-off of the Soviet debts, the successful launch of 'Two Bombs, One Satellite', the transition to environmentally friendly mining, and the development of heavy industry in China.