Bronze is an alloy of copper, tin, and a small amount of lead. Its appearance signaled the advancement in human culture from the Stone Age to the Bronze Age. For the approximately 2,000 years between the 17th century B.C. up until the Han Dynasty (206 B.C.-200 A.D.), the Chinese people used rare and precious bronze to cast large quantities of ritual vessels, musical instruments, and weapons that were elegant in form, finely decorated, and clearly inscribed with Chinese characters. They affirm the artistic achievement of ancient China, and demonstrate how early Chinese used their ingenuity to create works incorporating both science and art from resources in nature.