Cast iron kettle for the tea ceremony. Bell shaped, embellished by a thick rib decorated with a blossoming branch in relief. This type of teapot probably originated from the tedorigama, a domestic water kettle. The use of teapots in Japan grew in popularity during the Edo period in the second half of the 17th century, when Chinese merchants massively introduced the use of tea in China. The tea ceremony (chanoyu) involved the use of terracotta teapots up to the 18th century, when they were replaced by iron teapots which were used in simplified ceremonies (senchado), more suitable for a broader, growing audience.