Tiāngān zuì wǎn zài Xià Cháo yǐjīng kāishǐ, míngxiǎn de zhèngjù shì Xià Cháo hòuqī yǒu dìwáng jiàozuò Kǒng Jiǎ, yìn jiǎ.
Heavenly stems were already in use during the Xia Dynasty at the latest, where the first heavenly stem 甲 was named after the emperor Kong Jia (孔甲) in the late Xia.