Warrior Teapot in Blue (1.2L) Cast iron tea wares have been used for centuries for their functionality and alluring shapes. Known to keep the tea hot, cast iron also used to be prized for imbuing tea with additional iron content. TWG Tea cast iron teapots, however, are all enamelled to protect from rust and so that they can be used to prepare any variety of tea. Teapots are crafted in traditional shapes, colours and trimmings.