An experienced craftsman, Zhang began learning about making celadon-glazed pottery in a wood-fired kiln from his grandfather at the age of 18. The craft has been passed down through his family since the 18th century.

Many families in the village, like Zhang's, made their living from the traditional craft for centuries, but with the introduction of gas kilns in 2000, a technology that allows and ensures exact temperature control to produce porcelain with a high-quality glaze, use of traditional wood-burning kilns began to disappear.

"Gas or electrical kilns can ensure the quality of the celadon glaze. Craftsmen can predict what they get from modern kilns, as long as they set the right temperature. However, traditional kilns can offer unexpected surprises, which enamors makers and lovers of the craft," says Zhang, walking alongside the kiln, which is made of brick and clay and is more than 20 meters long.

He checks the temperature of the cooling kiln by touching the bricks, and is able to judge when it's the right time to remove the porcelain treasures inside.

The long kiln, shaped like a snake, can house dozens of vases or hundreds of tea cups. It takes 5,000 kilograms of wood and 12 potters to keep it firing for two days — a high cost in "both time and energy".