Chinese 25mm Cash coin 3.5g

I believe it's a 1 Cash, but can't recognise if it definitely is, or from when exactly.
.

Not far but not exactly
Here is your coin: https://en.numista.com/catalogue/pieces20859.html.
Many variants obverse/reverse are known.
Of the three Hartill references for this coin, yours would be #25.51 for obverse.

Thanks again.
In the Numista listing - going by the symbol printed to the right of the date in the "dates table" - am I right that the symbol on the reverse appears to show that as "C#1.2 - Kameido 1668-1700" ?

Citeer: "bmnobbs"​Thanks again.
​In the Numista listing - going by the symbol printed to the right of the date in the "dates table" - am I right that the symbol on the reverse appears to show that as "C#1.2 - Kameido 1668-1700" ?

​Yes this would be the "Bun" symbol on reverse for Kamedo mint.
If you look for "Bun" on this page http://www.history.ucsb.edu/faculty/roberts/coins/Kaneibasics.html, you'll find your coin with a picture too.