Celestial stem is an ancient
Chinese cyclic character
numeral system: Jia (甲), Yi (乙), Bing (丙), Ding (丁), Wu (戊), Ji (己), Geng (庚), Xin (辛), Ren (壬), Gui (癸). They were first used for dates in the
Shang Dynasty, and are now used with the twelve
Earthly Branches in the
Sexagesimal cycle in the
Chinese calendar and in
Chinese astrology. They are associated with the concepts of
yin and yang and the
Five Elements.
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