Metalworking, especially in bronze, develops throughout China. Tools, bells, and jewelry are among the earliest metal objects made. During the Shang dynasty (ca. 1600–1050 B.C.), a method of casting bronze using multiple ceramic molds was invented, resulting in the production of extraordinary ritual vessels intricately decorated in relief. This method, unique in the ancient world, required time and precision, and the control of the raw materials, labor, and technology was one of the prerogatives of the ruling Shang elite. Initially, Shang bronze workers imitated ceramic shapes and decoration; later in the dynasty, pottery began to reflect the influence of bronze ware, albeit on a smaller scale. Jade carving was another innovation that artisans of the Shang dynasty developed into a sophisticated art.