How to read a hare's fur glaze

Hare's fur is the oldest accident in tenmoku. Iron in the glaze gathers at the rim, then runs down the wall as the kiln cools; if the cooling is slow, the streaks are long and silver, if it is fast they stay short and brown.

Look at the rim first. A good hare's fur has a thin, bright line where the glaze pulled back — that is the iron concentrating. Then look at the wall: the streaks should start under the rim and thin out towards the foot, like rain on a window.

Two cups from the same firing will never match. That is not a defect; it is the record of where each cup sat in the kiln.