The list of ten Heavenly Stems (天干 pinyin: tian1 gan1) was an enumeration of discrete entities, as in years and dates often employed in Chinese astrology. It has been in use in China since the Shang Dynasty (1600 BC).
The phonetic characterss are:
- Jiǎ (甲)
- Yǐ (乙)
- Bǐng (丙)
- Dīng (丁)
- Wù (戊)
- Jǐ (己)
- Gēng (庚)
- Xīn (辛)
- Rén (壬)
- Guǐ (癸)
The Heavenly Stems are associated with Yin Yang
and the five elements
. They are matched with the twelve Earthly Branches
to form the 60 years cycles of Stem and Branch (干支) in Chinese calendar
The Branches are still used commonly nowadays in China in counting systems parallel to how alphabet is used in English, namely,
- Students' grades: with an additional Yōu (優 "Excellence") before Jiǎ.
- Choices on multiple choice exams, surveys, and etc.
- Vitamins' names (although currently, in this case, the ABC system is more popular)
- Organic chemicalss' names (e.g. Methanol=甲醇; Ethanol=乙醇.)
The kings of the Shang Dynasty
have characters of the Branches in their given names.
See also: Chinese numerals