Thanks. Of course, in order to do a ping test, I'd need another British East India Co. Rupee that I could trust.
For the moment, I'll chalk it down to a cleaning. The scratches don't really appear to the naked eye, but they do show up on the obverse in the photo. If someone else wants to lend or donate a proper Rupee for me to do a ping test, I'll gladly try it ! &

#128518;