Date
Governments usually require that their coins bear the date of issue. Some coin catalogs use circa to indicate an estimated date. Europe�s coins began occasionally showing actual calendar years in the late 1400s, often in Roman numerals, sometimes mixed with Arabic numbers as used today. A coin from Liege of 1484 was marked LXXX4.
Source: Numiscadero Spanish to English Glossary (Gary Beals)