These beigoma, or spinning tops, were a traditional craft in Sano City, Tochigi Prefecture, that dates back to the Heian period. (Tenmyo is an old place name for Sano City.) The tops are made with Tenmyo casting techniques, which were used to make items such as tea utensils when the tea ceremony grew highly popular in the Muromachi period,. Tenmyo casted tea kettles in particular were loved by tea masters all over Japan and gained an excellent reputation. While continuing to pass on traditional casting techniques to make tea utensils and copperware, Tenmyo craftsmen also began making more familiar products such as beigoma, which users cherish because of their unique texture and warmth in the hand.