Why did Chinese bronze workers use clay models and sectional molds?

Chinese bronze workers utilized clay models and sectional molds as part of a sophisticated casting process that showcased an early mastery of the ceramic medium. This technique was employed for several key reasons:12

• Precision and Detail: By incising patterns directly into the mold sections, artisans could transfer fine, intricate designs onto the bronze surface. This allowed for a double transfer—from clay to metal—or the creation of raised designs by incising the mold in reverse.12
• Structural Complexity: The sectional-mold method enabled the creation of complex vessel shapes. By assembling mold pieces around a central core (separated by metal spacers), workers could cast hollow objects with consistent wall thickness.12
• Modularity: The process allowed for the separate casting of appendages such as legs, handles, and sculptural elements, which were then integrated into the main body using a "lock-on pour" technique.12
• Technological Advancement: This method allowed for the production of large, heavy, and highly decorated ritual vessels, demonstrating a level of technical sophistication that made Chinese bronze casting the most advanced in the world by the end of the 2nd millennium BCE.2