Is there such a thing as a 1/16 Karshapana because this little punch marked copper coin is light enough to qualify. Or is there another denomination that covers coins of this period weighing 0.50g?
Here is the Indian coins Weight denomination standards from Mitch's ACW. I have highlighted the part that interests you.
According to this 8.5 grams was 1 Karshapana. So you could make out the denominations. But the weight was not very accurate for the hammered coins so it's always relative and not exact.
Hope this helps.
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