Teaware materials

The material decides how fast a vessel heats up, whether it picks up smells, and whether you can see the leaf through the wall. That is how it gets matched to the job: clay for oolong, glass for green tea, iron for water.

Most teaware is fired clay, and in China it falls into two families. Pottery (tao) stays porous and holds heat: Chaozhou shoula teapots, Jianshui zitao, nixing from Qinzhou, Rongchang ware. Porcelain (ci) is fired hotter, so the body vitrifies and absorbs nothing. This family includes Jingdezhen porcelain, made there by the imperial factory from 1369, Dehua white porcelain, the celadons of Yue and Longquan, and the black jian zhan bowls of the Song.

Glass is chosen for transparency: you can watch the leaf open and the liquor darken. The oldest find, a tea set from Famen Temple, dates to 874. Borosilicate 3.3, marked «耐热», takes boiling water, while a thick tumbler of ordinary glass may crack. Glass works best for delicate green, yellow and jasmine teas.

At the tea table, metal mostly means boiling water: in a Japanese cast-iron tetsubin, or in silver and hammered copper kettles, the copper ones always tinned inside. A tetsubin adds up to 0.03 mg of iron per liter. Tin melts at around 230 °C and never goes on the fire, but a tin caddy keeps dry leaf well.