Muhammad bin Tughlaq’s experiment of introducing token currency could not succeed on account of

Muhammad bin Tughlaq introduced token currency in 1329–1330 CE, issuing copper and brass coins with the same legal value as silver tankas [1]. This progressive experiment failed primarily because the state lacked a monopoly over minting, and the design of the coins was too simple to prevent forgery. Consequently, large-scale minting of spurious or fake coins occurred, with many households reportedly turning into private mints [1]. These counterfeit coins flooded the market, leading to a devaluation of the currency and a breakdown in trade [1]. While foreign merchants did eventually reject the coins and the economy suffered, the root cause of the failure was the government's inability to prevent this massive influx of forged currency [2]. Ultimately, the Sultan had to withdraw the experiment and exchange the token coins for genuine gold and silver from the royal treasury.

Sources

1. [1] History , class XI (Tamilnadu state board 2024 ed.) > Chapter 10: Advent of Arabs and Turks > Tughlaq's Coins > p. 145
2. [2] https://berhamporegirlscollege.ac.in/uploads/2048UG2-Sem-History-Hons.-on-Muhammad-Bin-Tughluq-Vipul-Singh-04-06-2020.pdf