Now with decades of practice, Nie can tell whether the hole is deep enough by the sound of drilling.

"We used to make the hole with a diamond by hand, but now with the drill, the size of the hole can be better controlled, and it's easier to teach others," he says, adding that the electric drill can make a hole as small as 0.3 millimeters.

Nie says the technique and tools should be preserved.

Due to the availability of modern manufacturing, people prefer to buy a new object instead of repairing a broken one. The need for the skill has become increasingly rare in modern times, yet to repair ceramics, training and practice are needed.

Nie says repairing ceramics is now such a niche field that he can't even make ends meet. He is making ceramics himself and doing repair work when needed. But he insists on continuing with the traditional skill. He says he hopes to utilize it as a "process of inheritance", and tell more people how the repair is done, so the technique won't vanish.