Their primary purpose was as a religious token, amulet or charm, Figleaf, for which the weight was not crucial, and varied a bit. If modern collectors are fooled into buying a few of the solid silver ones as rupees (and who among us wasn't, when we first started collecting?) it is reasonable to presume that some people in Mughal times might also have been tricked into accepting tokens of reasonable weight as rupees from time to time. Like so many questions, Figleaf, unless the matter is dealt with in some contemporaneous travellers' tales or if 'The Ain' or similar has nothing to say about it, we could only be certain of the facts if we had a Time Machine and travelled back to Akbarabad, Mahayetigarh or Yogibearpur bazaar and watched what was going on. Probably the brass-cored ones would soon have been found out and discarded, along with the hand of the one tendering it to pay his taxes.
However, just because you and I have not noticed any reference to such transactions, doesn't mean there are none, so maybe somebody can tell us more about it? As Abhay said earlier this week, Oesho carries two libraries in his head!
Salvete
