He has felt the responsibilities weighing on him of carrying forward the art over the years, as senior craftsmen, who used to be his teachers, are gone, but he is delighted that more people have come to his school to pick up the craft.

Over the past 20 years, the school offered training to more than 1,000 students of all ages, including students from Mongolian and Tibetan ethnic groups, as well as professors from countries such as Mongolia and the United States.

Yan Hui, from Southwest China's Guizhou province, has followed Liu to study and practice white marble carving since 2013.

"I was interested in carving seals before and decided to hone my skills after I saw the school was enrolling students," says the 29-year-old.

Years of learning has exposed him to the charm of the craftsmanship and Liu's meticulous work attitude and sense of perfection in the trade.

"Liu would go over a piece of work through a fine-tooth comb and make improvements over and again until it is perfect," Yan notes.

It has influenced Yan, who says he would work with Liu to help carry forward the art.

Liu says he couldn't understand his own fascination about white marble. "If you asked me 20 years ago if I will commit myself to the art, I honestly couldn't be sure," he says.

However, he has found an ongoing dialogue with the stone in the process.

"The variations in white marble are endless. To understand its properties, you have to contend with its flaws," Liu says.

"In some cases, I was carving a piece for months, and suddenly a flaw appears, threatening to render my previous efforts in vain. The only thing I could do is to fight with it, and each time I do, I understand it a little more."