故宫古建修复还需“金砖”、金箔？ | Why is the Palace Museum repaired using gold?

It's no surprise that the Palace Museum shows up at the top of the search results. As the world's largest ancient palace complex at the heart of the Chinese capital Beijing, its use of "gold bricks" and "gold foil" for repairs captures the public imagination.  

Earlier this month, the Palace Museum accepted a donation of 100 gold bricks and a million pieces of gold foils from the Tai Hu World Cultural Forum. Curator Shan Jixiang said all will be used for the ongoing repair efforts for the museum.

"It is today's present for the future, for the Forbidden City's next 600 years," said Shan at the donation ceremony. He added that not only are the gold materials necessary for the repairs, but they must be provided by a certain company. Bidding will not work here.

Curator Shan Jixiang examines gold bricks donated to the Palace Museum. /VCG Photo 

The bricks and gold used in the palaces

In fact, the gold bricks are not made of gold. It is a type of specially made large brick used for construction and repair in the Forbidden City, which was once the residence for Chinese emperors. 

What distinguishes the gold bricks from the ordinary ones is how they are made. According to records, it requires at least 29 procedures and at least a year to make a batch of gold bricks. Even then, only 20 percent of the bricks produced will be up to standard.

Gold bricks and gold foils piled up at the ceremony. /VCG Photo

In the past, Suzhou city was where the main imperial kilns were located. Today, the ancient craftsmanship has been preserved in the area. However, due to its long production periods and high costs, such meticulous efforts are no longer suitable for mass production. Instead, it is now categorized as a national intangible cultural heritage.

Shan Jixiang said there used to be bidders for the repair efforts, but the quality of their bricks were not up to par, until the Lumu imperial kiln factory came along, which was later designated the official supplier of the gold bricks.

It is the same with the gold foils as well, which were mainly used for the restoration of the decorations. It required high purity of 74 to 98 percent, and at least 12 procedures. The thickness could not exceed 0.15 microns.

The ancient palaces under repair work

The Palace Museum in repair. /VCG Photo‍

The current repair work of the Palace Museum was authorized in 2002, with the goal of enabling the ancient relics to remain stable as of 2020. It is the largest-scale repair efforts for the palaces since 1911, when the last dynasty of Chinese feudalism ended.

But the repairing techniques and materials remained a problem for the quality of the project. In recent years, the State Council has listed the official construction techniques and craftsmanship for ancient structures in the national intangible cultural heritage. The Palace Museum also set up an institute to study the materials and techniques.

The decade-long repair work is approaching its end, but no matter how many times the palace must be repaired, protecting the cultural and historical relics remains the utmost priority, said the curator.