Page 10 in this online PDF of Coole's "Coins in China's History" states that "mei" is "a copper or brass coin equal to ten cash": https://ignca.gov.in/Asi_data/19162.pdf
And the coin itself states 10 wen on the obverse and 1 mei on the reverse.
I hope that is useful.
And the coin itself states 10 wen on the obverse and 1 mei on the reverse.
I hope that is useful.






















