Decimal Day and 10p coin equivalents, co-existed in circulation as valid currency until the early 1990s. In theory this included coins dating back to 1816; in practice the oldest were dated 1947, when these coins stopped containing silver. The coins were withdrawn when smaller 5p and 10p coins were introduced in 1990 and 1992 respectively. The face value of Maundy money coins was maintained, increasing all their face values by a factor of 2.4, as the coins continued to be legal tender as new pence. The numismatic value of each coin, though, greatly exceeds face value. The decimal halfpenny (p), introduced in
Decimal time He also suggested a week of 10 days and dividing the year into 10 "solar months". Decimal time was officially introduced during the French Revolution. Jean-Charles de Borda made a proposal for decimal time on November 5, 1792. The National Convention issued a decree on 5 October 1793: These parts were named on 24 November 1793 (4 Frimaire of the Year II). The primary divisions were called hours, and they added: Thus, midnight was called either "dix heures" (10 o'clock) or "zero heures" (0 o'clock), noon was called "cinq heures" (5 o'clock), etc. Units were either written out or abbreviated,