Choosing a teapot that will last twenty years

Two pots can look identical and behave completely differently over a decade. The difference is the clay and the finish.

Original-ore Yixing clay is unglazed. It is slightly porous, and it takes on the tea you brew in it — which is why a pot used for one kind of tea for years starts to smell of that tea even when empty. A blended or glazed pot cannot do this.

That is the whole argument for unglazed original ore: it improves. A glazed pot stays exactly as it was on the day you bought it, which is fine for a serving vessel and wrong for a brewing one.

When you buy, ask what the ore is, whether the exterior is glazed, and who threw it. A pot that comes with no answer to those three questions is a pot you will replace.