Must a Gaiwan Fit Perfectly?

When we hold a Yixing teapot, we are often amazed by how seamlessly the lid fits with the body. This is indeed a testament to the potter’s exquisite craftsmanship. Made entirely from the same clay and fired without glaze, a Yixing teapot shrinks evenly in the kiln, resulting in that perfect snug fit.

By contrast, very few gaiwans can achieve such precision. When comparing a gaiwan to a teapot, the gaiwan often loses out in terms of tightness. But why is this so?

The main reason lies in their materials and firing process. A Yixing teapot is made purely from clay; both body and lid use the same material, unglazed, and thus shrink consistently during firing. As long as the potter masters the dimensions during crafting, the finished teapot almost always fits perfectly.

A gaiwan, however, is different. In addition to the clay body, it is coated with glaze before being fired at high temperatures. Because clay and glaze shrink at different rates, and because firing temperatures vary within the kiln, uneven shrinkage is inevitable. Achieving identical shrinkage between the clay body and glaze is extremely difficult—matching the lid and bowl, which may sit in different parts of the kiln, is even harder. Only by using small-kiln precision firing, like with Yixing teapots, could this be improved—but then the cost would skyrocket.

In truth, the very form of the gaiwan ensures that slight misfits are natural and lasting. For beginners, a loosely fitting gaiwan may actually be better. If the lid fits too tightly, it creates strong suction after pouring, making the lid difficult to lift. Worse still, once sealed, tea may not flow out smoothly—the leaves get locked in, the infusion overheats, and while trying to pour, you may scald your hand without even draining the tea.