This is a Vietnamese coin of unknown date of issue. Due to the country’s frequent historical periods of political fragmentation, and even during times of dynastic unification, regional warlords and local elites often engaged in the independent minting of currency. Within this socio-political context, numerous coins emerged that cannot be correlated with any officially recognised reign title. Such coins are referred to in numismatic scholarship as “uncatalogued coins” (脫譜錢), denoting currency that falls outside the established historical and administrative records.
The coin follows the traditional Chinese-influenced square-holed cash coin design and is made of bronze. On the obverse, the four Chinese characters “Thiên Thánh Nguyên Bảo” (天聖元寶) are arranged in a clockwise sequence. The character “Nguyên” (元) at the bottom is rendered in seal script, while the other three characters are written in regular script. This blending of different calligraphic styles is a common characteristic of Vietnamese coinage.
The reverse side of the coin is blank, without any inscriptions or decorative elements. However, it still bears residual impressions from the casting process, suggesting that the coin mould was misaligned during production, resulting in overlapping traces of two coin patterns on the reverse.
“Thiên Thánh Nguyên Bảo” (天聖元寶) was directly modelled after the “Tiansheng Yuanbao” coins issued under the first reign title of Emperor Renzong of the Northern Song dynasty in China, used between AD 1023 and 1032. Given this temporal reference, the Vietnamese imitation of this coin could not have been minted earlier than the Lý dynasty period in Vietnamese history (AD 1009–1225).
