The correct answer is development of bronze metalworking. The Shang dynasty (1766 b.C-1122 b.C) was the second dynasty of China and by archaeological finds of vessels, hieroglyphics and tools it was determined that they had advanced techniques to handle bronze. In this dynasty the bronze was used for the realization of objects very well elaborated as much religious as daily and it is said that the metallurgy of the bronze of this dynasty was the most advanced of the world. The establishment of the silk route corresponded to the Han dynasty (206 b.C - 220 b.C) and metal coins emerged in the period between 770 b.C - 476 B.C, in the Shang Dynasty it was more common to use shells as currency.
