Five various punchmarks / Blank. 23mmx23mm, 3.35 grams. Gupta and Hadraker (2014) #50.

HUGE silver planchet, rare 1st issue karshapana. 

A wonderful huge silver coin from the lifetime of Buddha. First issue Karshapanas are very rare, and are hard to find. The date when these coins started being issued is most obscure. It is fairly certain that by ca.470 BC the large flat karshapanas such as this coin were replaced by karshapanas of the same weight but struck on smaller, thicker flan. So the tentative dating of these coins is ca.550 BC (when the first coins of this type were produced) until about 470 BC, when they were replaced by type II karshapanas.