The Sound of an Yixing Teapot

(Originally published November 1, 2020)

Can you tell if an Yixing Teapot is real by banging the lid against the body? What does a real Yixing Teapot sound like? Should zhuni ring like a bell?
 
We sometimes receive questions about one famous method for checking the quality or authenticity of a teapot – dragging or knocking the lid against the body of the teapot. The pitch, ring, etc. is supposed to tell the listener something about the pot.

We do not recommend tapping the lid against the body of the pot because: 1) you may damage the teapot! 2) It isn't very useful. In fact, you can tell very little about a pot by banging the lid against it. The sound of a teapot will be affected by a number of factors that have nothing to do with clay quality, including:
 
1) The thickness of the pot.
2) The size of the grain of the zisha.
3) the shape of the pot.
2) the firing temperature of the clay.
4) whether or not the teapot has been used before.
 
 There isn’t just one acceptable sound for an Yixing Teapot.
 
Why Check the sound?
However, there are a couple of good reasons for checking the sound of a teapot by gently (very gently!) tapping it with the lid.
 
1) To check that the teapot was fired at the right temperature.
2) To check for cracks that may not be visible.
 
Firing Temperature
The first reason should not be a concern for most people in the market. When Yixing Teapots were fired in dragon kilns, a stable and appropriate firing temperature was a concern for potters. The potters would check that the kiln had fired the clay at the appropriate temperature by tapping the body of the teapot with the lid. They were experienced firing pots of various shapes, sizes and clays, and could tell if the sound was off. They also checked for the flat sound of a cracked teapot, one that was damaged during firing.
 
Hairline Cracks
Checking the sound of a teapot was and is used by some antique Yixing Teapot collectors to identify cracked teapots. A cracked teapot will have a flat sound. While checking the sound of a teapot for cracks makes sense, it is not a good indicator for clay quality in an undamaged teapot.
   
Ringing like a Bell
Beware the teapot salesman who says you can tell the quality of his pot by its bell-like ring. Besides the fact that the pitch of a teapot will vary depending on the factors listed above, clay can have other elements added to give it a more obvious metallic ring.
 
For readers who can understand Mandarin, the video below by Zhuang Zhuang Zisha
 庄庄紫砂 is a good guide for when it makes sense to check the sound of a teapot and when it does not.