Vic, were the round ones not cut from bars? If that was so, would these not have been cut from square bars? Much more difficult to make as compared to the round ones.
Amit
It is the cutting method that concerns me, as someone who dabbles in metalwork myself I think cutting flans from big round sausage shaped bars would be a major task back then, you just could not chop a thick silver bar into slices so they would have to use a saw of some kind, no high speed steel blades either so even the blades would have to be made by hand. Rupees usually show a reasonably smooth flan behind the inscription, cutting a bar in any metal with a hacksaw leaves a very scarred surface so how would they remove that.
I always thought they were cut from sheet silver and beaten into shape, perhaps this explains why Rupees often have a many faceted edge, evidence of numerous hammer knocks
In W.W. Webb's 'currencies of Rajputana' he visits numerous mints and describes watching them 'making silver sheets & cutting into proper weight' forming & stamping the coins etc. Although a later era than the Mughals should we presume the same practices continued into later centuries?