China 10 Cash, Hupeh - Variant And Dating?

Thanks. Undated, the auction description was correct. Mine's size and weight also seem good, 7.16 g with some wear.

I see Y#122.4 there again. But no explanation about where they get that reference from

Thank you. I will wait and see what new information about these coins people add to that site Numista. Seems a work in progress. Someone will one day place there the explanation about where that reference Y-122.4 comes from.

It's a little more complicated. Yes, Y stands for Yeoman.

The Yeoman books are: Modern World Coins (covering 1850 to 1964, most recently published in 2023, the previous version was 2008) and Current Coins of the World (covering 1964 and later, last published 1988).

But Krause adopted Y numbers for many countries. Some have been replaced with KM numbers, but for China only some of the numbers have been replaced.

And for the complication: In many places Krause has added sub-types. For example splitting Y# 1 into Y# 1.1 and Y# 1.2. In those situations you will only see Y# 1 in a Yeoman book -- you need to read a Krause book to understand the difference.

(If you look at Numista you will see Y# connected with Yeoman books. The fact that the numbers actually come from Krause and not Yeoman isn't mentioned.)

Ultrasonic cleaning, possibly followed by gentle use of a toothpick, might remove some of the surface impurities without damaging the coin. I would not polish the coin - it would ruin the patina and might leave scratches. I also think it's fine to just leave the coin as it is.