These coins can be identified further by minor variations in the calligraphy, if you are so inclined. This can tell you the years the coin was minted and the province. I have looked through my book and can't find an exact match. I have a big handful of these coins and maybe 30ish% can't be definitively attributed.
There is no mintmark, so that eliminates many coins.
The 3 o'clock character is kind of mushy, which doesn't help.
Some of these coins contain enough iron to be magnetic, which would help in narrowing down an ID further.
Your coin can at least be classified as a 'New Kanei' putting it at 1668 at the earliest.
The book I use is David Hartill's
Early Japanese Coins, which I recommend to everyone with an interest in Japanese coins. It covers these 1 mon coins in addition to the 4 mon, tempo tsuho, ichi bu, isshu, bita sen, etc - basically everything up until modern minting began in the 1860s/1870s after the Meiji restoration. The book is available
at amazon or
at the publisher's website. Cheap as far as coin books go, and very good value.
I have tried to upload an edited image showing the distinctive markings:
-wheatiefan