1 Ouguiya

Mauritania's ouguiya has the unusual distinction of being one of the few modern currencies not based on decimal subdivision — the traditional unit divides into 5 khoums, a system rooted in pre-colonial exchange practices that the country retained at independence in 1973. This bimetallic-era coin was replaced in 2018 when Mauritania redenominated its currency by a factor of ten, issuing a new ouguiya equal to ten old ones. The piece dates from the final transitional window of the old system.