Chhatarpur (Princely State of India) -- but which coin? what date? [solved]

18.5mm, 11.1 grams, silver

It seems clear to me that this is a coin from Chhatarpur.  It looks very similar to KM# 15.1 (especially because of the trident on the obverse), but also differs from #15.1 because the coin I have is 18.5mm, not 20.5 (and the coin I have has sharp edge lettering, so it's not just the case that this coin has been worn down). And the date of this coin doesn't seem to fit (unless I'm reading this coin wrong – which is very likely). I've checked Zeno and Krause (late 1700s and early 1800s) and am still not certain which coin this is.

Thank you for your help.

I think you are correct that this is a Chhatarpur silver rupee. The date appearing at the bottom of the first photo is AH 1199 (approx. AD 1786), with the two nines retrograde. I found another example of a Chhatarpur rupee with a retrograde nine. 

N#160273

The regnal year, at about 4 o'clock on the second photo, is 26, which for Shah Alam II (who acceded to the throne in 1759) would be about 1785 so in agreement with the AH date. 

Here's an example of one with the trisul, also identified as KM #15.1.

https://www.marudhararts.com/printed-auction/auction-no-18/lot-no-283/coins-of-india/indian-princely-states/chhatarpur-state/1-shah-alam-ii-1759-1806-/silver-one-rupee-coin-of-chhatarpur-state-.html

It appears that your year is not listed in Krause. This happens fairly often. 

I would not worry about a two-mm variation in diameter, because there is considerable variability in hand-struck coins. 

Thank you so much for your help Seeker. Thanks for explaining the retrograde nines, and the reminder about diameter variance on hand hammered coins, and the note about the commonality of RYs not being listed in Krause. Putting these things together makes the identification of this coin seem pretty clear. Much appreciated.

For details about Chhatarpur coins refer “Some aspects of the History and Coinage of the Panna Area” by Barry Tabor

https://fdocuments.in/document/aspects-of-panna-coinage.html?page=1