The donative 1/3 siliqua is a fascinating and exceptionally rare denomination from the Late Roman period that reflects the intersection of monetary innovation and imperial ceremonial practices. These coins were struck in 330 AD at Constantinople under Constantine I to commemorate the formal founding or dedication of the city of Constantinople. These tiny silver coins represented one-third of the standard siliqua, with the denomination sometimes being referred to as a scripulum. The commemorative third siliquae are among the most interesting Roman coins, with the types representing Constantinopolis with a large K. These were not regular circulation coins but rather special donative issues distributed on ceremonial occasions, following the Roman imperial tradition of largesse. Their importance today, with some types known from only a handful of specimens, combined with their small size, makes them fantastic additions to any collection.