The art of blowing beautiful bubbles

Arrays of delicate liuli (colored glass), ranging from vases and teacups to snuff bottles, glitter in the light at Sun Yunyi's studio in the Boshan district of Zibo, Shandong province.

The pieces in a distinctive oily yellow tint that resembles the fat in an elderly hen's abdomen are particularly striking. They are known as jiyouhuang (chicken-fat yellow).

These exquisite yellow liuli emerged during the Ming Dynasty (1368-1644) and were mostly produced during the Qing Dynasty (1644-1911). The color was reserved for the imperial family thus earning nicknames like "Imperial Yellow "and "Yellow Jade".

Over time, research and surviving artifacts related to its production were lost, making it an increasingly rare historical treasure, and jiyouhuang became prized by generations of collectors for its intricate craftsmanship.

Using scraps of information from his forebearers, who used to work in the royal workshop, Sun and his family managed to rediscover the way jiyouhuang was made in 2007, after much trial and error.

This achievement set him apart from other practitioners in Boshan, which has been making liuli for more than 2,000 years.

About 2 kilometers away from his studio, the deep hum of a kiln and a stark rise in room temperature at the production site give a hint of the toil behind the stunning artworks.

With a focused look and steady hand, Sun grasps a blowpipe and extends it into a crucible heated to over 1,300 C.

He stands tall, heat radiating from the furnace, his hands skillfully stirring the molten glass, before lifting the blowpipe.

As he blows forcefully into it, the fiery-red lump of colored glass on its end expands, forming into a perfect, round shape.

"Blowing is a crucial step in the process of making colored glass and determines its shape," Sun says.

"Since the colored glass must be heated repeatedly, and the blowing process needs to be done multiple times to achieve the desired shape, there's no fixed standard for the process. Every piece requires careful judgment, and liuli makers must adjust the heat and blowing technique as needed, relying on their intuition and expertise to perfect the shape," he adds.

As the glass begins to cool, its brilliant red hue shifts to a rich, deep crimson.

Using a shaping board, Sun begins gently tapping the still molten glass, molding it into a smoother, more defined form before switching to other tools, rolling and rounding it with care.

Finally, using a pair of gourd-shaped tongs, he cuts the glass from the pipe, producing a semifinished piece of jiyouhuang.

After several hours of cooling in an annealing kiln, the color takes on a yellow hue.

Following the annealing process, the piece is polished using grinding wheels to create a smooth surface, and then patterns are carefully engraved onto it before being filled with color.

"Each step must be executed in one continuous motion, leaving no room for error," Sun says.

He threw himself into production right after the Spring Festival holiday.

"We still have orders from last year that are yet to be delivered," he says, adding that demand for liuli is on the rise.

He and his team have also come up with new designs and forms to meet ever-changing market needs.

For the Year of the Snake, he has drawn inspiration from xuanwu, a fabled creature in ancient Chinese mythology composed of a tortoise intertwined with a snake.

He has ingeniously inset a snake figure in the belly of a tortoise after overcoming challenges such as the snake's tendency to deform or melt during secondary heating.

Sun says that as the tortoise is a symbol of longevity and endurance in Chinese culture, and the snake is often associated with regeneration and rebirth, the piece is imbued with an auspicious symbolism that makes it very popular.

Other liuli pieces, including pendants and brooches, have all been very well-received by younger consumers.

Born into a family of liuli artisans, Sun was predisposed to the art from observing his grandfather and father working amid the flames as he played with liuli marbles.

In 1983, he was making pieces at a factory, where he learned the art of painting on snuff bottles and making liuli art.

"The colored glass industry is one in which you seek wealth in the flames. The working environment is harsh. In the summer, the temperature in the workshop can exceed 40 C, and furnace workers often work shirtless, even in winter," he says.

As he built up his expertise, Sun decided to bring back the glory of jiyouhuang when his family set up their own small liuli workshop in the 1990s.

There was no surviving documentation of the full formula and composition of jiyouhuang, and each ingredient required research and experimentation.

"The formula we found generally mentioned white materials, such as aluminum oxide and quartz, but there was no hint of how much of each was needed. It also mentioned gray-colored substances like arsenic, but again, the exact composition and the precise amount of each component were not specified," he says.

Initially, the success rate was low.

"Nine out of 10 attempts were usually failures," Sun says. "Factors such as the quality of the raw materials, the control of the firing temperature, and even the climate, can significantly affect the final quality."

As if under a spell, he burned through the family savings and eventually filled in the missing information after years of endeavor.

He explored the use of other raw materials to improve the recipe, and upgraded both craftsmanship and techniques accordingly to refine the formula for jiyouhuang, giving rise to a much higher success rate and purity of product.

To ensure that only the finest pieces are created, Sun follows strict standards: if there are any bubbles or deviations in color, the product in question is immediately discarded.

According to evaluation by the Palace Museum in Beijing, his jiyouhuang pieces surpass the Qing Dynasty originals in quality.

In 2013, Sun became a national patent holder for the jiyouhuang production method, and the craft was named a provincial intangible cultural heritage in Shandong in 2016.

Many of his pieces have made their way to collectors, including in the United Kingdom, Australia and the United States.

Wang Feng, who switched to liuli design and sculpting in 2012 after being stunned by Sun's work, is now his apprentice.

"The jiyouhuang pieces are just extraordinary, and I can sense the rise in popularity of liuli over the years," says Wang, who is in his 40s.

He apprenticed with Sun in 2018, when he started to add creative touches to the natural patterns of his pieces.

"His friendliness toward people around him, patience in answering technical questions, and rigorous control of quality are nothing if not impressive," Wang says.

In addition to continuing to upgrade production and quality, Sun has paid equal attention to keeping up with market trends.

He believes that the art of liuli must explore new uses and contexts to broaden its appeal.

"We are constantly influenced by market demands and the aesthetic preferences of buyers to explore new possibilities, such as jewelry and cultural creative products. This way, we can integrate this national treasure into the daily lives of countless households," he says.