50 Rupees

Ceylon's Central Bank issued this denomination through a period of acute political tension — the 1970 election brought Sirimavo Bandaranaike back to power with a sweeping mandate, and the economic nationalism that followed would eventually lead to the 1972 republican constitution and the renaming of the country itself. Notes of this series, still reading "Ceylon," had a limited window before the issuing authority's name became obsolete.

Thomas De La Rue's involvement was long-standing with Colombo, though pressure to shift security printing to local facilities intensified through the early 1970s. The P#77 series predates that transition.