How ancient Chinese bronzes were created

Summary

In this video from the Arthur M. Sackler Museum at Harvard, Dr. Robert Mowry, the Alan J. Dworsky Curator of Chinese Art, discusses the intricate technology behind Shang dynasty bronzes. These ancient artifacts were crafted using a complex piece mold technique unique to this period. The process involved creating a clay model, making sectional molds, and carving decorations directly into the model. The molds, fired to withstand molten bronze, had to fit perfectly despite clay shrinkage. This sophisticated method, which minimized post-casting work, resulted in exceptionally detailed and durable bronze vessels.

Takeaways

• 🏛️ The discussion takes place at the Arthur M. Sackler Museum of Harvard Art Museums.
• 👨‍🏫 Dr. Robert Mowry, the Alan J. Dworsky Curator of Chinese Art, has been at Harvard since 1986.
• 🗿 Harvard's Chinese art collection includes extraordinary bronzes from the Shang dynasty.
• ⚙️ These bronzes were made using a unique piece mold technique not used elsewhere until possibly the 20th century.
• 🎨 The process starts by making a clay model of the vessel, which is then fired to give it strength and durability.
• 🖼️ Clay pieces are applied to the vessel to create the mold, hence the term 'piece mold.'
• 🔨 The decoration was integrally cast with the vessel, with little to no post-casting work.
• 🔥 The mold pieces are fired, which causes them to shrink, and they must still fit together perfectly after shrinking.
• ⚖️ Inner molds were used to ensure vessels were hollow, supported by bronze chaplets.
• 🔄 The casting was done upside down to allow bubbles to rise to the bottom of the legs, where they wouldn't be visible.

Q & A

Who is Doctor Robert Mowry and what is his role at Harvard?

Doctor Robert Mowry is the Alan J. Dworsky Curator of Chinese Art at Harvard and has been working there since 1986.

What is one of the extraordinary features of Harvard's Chinese collection?

One of the extraordinary features of Harvard's Chinese collection is a series of bronzes from the Shang dynasty.

What technique was used to create the Shang dynasty bronzes, and why is it significant?

The technique used is called the piece mold technique, which is significant because it was very complex and unique to ancient China, not seen elsewhere in the world until possibly the 20th century.

How was the initial model for the bronze vessel created?

The initial model for the bronze vessel was made from clay, which was fired to provide strength, durability, and a hard surface.

What is the 'piece mold' technique and why is it named that way?

The 'piece mold' technique involves making molds in multiple small pieces by pressing clay against the fired model of the vessel, which is why it is called 'piece mold.'

How was decoration added to the bronze vessels?

Decoration was carved into the clay model before molding. This decoration was integrally cast with the vessel, meaning it was part of the casting process rather than being added afterward.

What does 'integrally cast' mean in the context of these bronze vessels?

'Integrally cast' means that the decoration was cast as part of the vessel itself, with little to no post-casting work such as chiseling or engraving.

What challenges arise when firing the clay mold pieces?

When firing the clay mold pieces, they shrink, and the challenge is to ensure that the shrunken pieces still fit together perfectly for the casting process.

What are chaplets and what role do they play in the casting process?

Chaplets are small pieces of bronze used to hold the inner mold away from the outer mold during the casting process, ensuring the vessel doesn't become solid.

Why was the vessel cast upside down, and what problem did this solve?

The vessel was cast upside down to ensure that any bubbles in the molten bronze would rise to the bottom of the vessel's legs, where they wouldn’t be visible.