Coins and Banknotes of Vietnam and French indochina

Vietnamese Calendar

Vietnamese Cyclic Chronology
stem-branch
cycle 
Or:

Eastern calendar is based on two cycles:
  • the cycle of ten Heavenly Stems, associated with Yin/Yang and Five Elements, and
  • the cycle of twelve Earthly Branches, associated with twelve animals of Asian Zodiac.
Together, these cycles form a 60-year stem-branch cycle. Two cyclic characters in combination with two (sometimes more) characters of the Reign Title indicate the exact date.

Example - how to date the silver bar:

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