1 Rupee Rajiv Gandhi, mule

A mule in Indian coinage terms here means the obverse die from one issue was paired with a reverse die from another — an error of assembly at the Bombay or Calcutta mint rather than intentional design. The year 1991 is significant: Rajiv Gandhi was assassinated on 21 May of that year, and commemorative rupee issues were hurried into production under difficult administrative conditions, creating exactly the kind of die-management pressure that produces mule errors.