Current usage of the Heavenly Stems
One system by which years are marked historically in China was by the stem-branch or sexagenary cycle, a cyclic numeral system of 60 combinations of the two basic cycles, the ten Heavenly Stems (天干; tiāngān) and the twelve Earthly Branches (地支; dìzhī). Each year is named by a pair of one stem and one branch called a Stem-Branch (干支 gānzhī)...more
Relations between Chinese sexagenary cycle and Western calendar
Intro to the twelve Earthly Branches