It's a Bull
and Horseman jital, made by many kingdoms for many centuries before, during, and a little after the Islamic
conquest of most of India
. The only dedicated resource is "Jitals" by Robert
Tye; he has made the plates free to download for easy reference.
I don't see enough of a legend
to allow an attribution
beyond "late anonymous type
". Not sure of silver purity, but genuine examples are worth only a couple dollars, so I don't doubt its authenticity. They are very common coins!
Here is the prototype: