Dating old chinese coins
Knives were a common barter item in ancient China, but a bit hazardous to carry around to trade.
Some of China's first coins were made to look like a knife, so that people would think of them as money, but they lacked a sharp blade. This knife coin is called the "Ming" after the city where it was made (not the dynasty that was much later).
The second step to dating your Japanese coins is to determine which emperor the coin was minted under. 2) of each emperor from the beginning of the 19th century to the present day.
The characters for the name of the emperor’s reign can appear in either orientation as shown in the chart.
The earliest Chinese coins were cast in bronze—by the 1st century BCE, these round coins featured square holes in their centers.
This style persisted until about the 13th century, when silver and then brass coins were minted and circulated.
Japanese coins can be dated either in Japanese numerals or Arabic numerals.
Because of the relatively low value of the coin and the high level of commerce a LOT of the coins were issued during that period.
(Think of doing all your transactions with only pennies!
In order to determine if they use that method or the Western method (left to right), simply look for the Japanese symbol nen, meaning year (fig. Nen always follows the date, so by using that you can determine which way the date is written.
NOTE: For the first year of the reign of an emperor, the Japanese character gan is used in place of the numeral for 1.