The tamlung (or tamlueng) denomination — equal to four baht — had deep roots in Thai monetary reckoning but was rarely struck in Western-style coinage. This 1869 pattern was part of the Royal Mint's broader effort under Rama V to transition Siam away from the bullet coinage (pod duang) that had served as the primary circulating medium for centuries. The copper-nickel composition was experimental for Siam at this date; no regular-issue tamlung in this metal entered circulation, and KM#Pn32 exists precisely because the composition was ultimately rejected.
The tamlung (or tamlueng) denomination — equal to four baht — had deep roots in Thai monetary reckoning but was rarely struck in Western-style coinage. This 1869 pattern was part of the Royal Mint's broader effort under Rama V to transition Siam away from the bullet coinage (pod duang) that had served as the primary circulating medium for centuries. The copper-nickel composition was experimental for Siam at this date; no regular-issue tamlung in this metal entered circulation, and KM#Pn32 exists precisely because the composition was ultimately rejected.