A traditional Japanese style of teapot, the tetsubin is made of intricately-decorated cast iron, often finished in striking colors. The interiors of these teapots are finished in porcelain enamel to avoid corrosion and each includes a stainless-steel mesh tea infuser. Although made of iron, a tetsubin is designed for steeping tea, not for heating water on a stove or other burner. 20-oz. capacity.