I bought this coin and i noticed something on the reverse. Instead of it having 3 I it’s has 4. I was just wondering why it has 4 instead
TRP is the office of Tribune of the people and it means the 4th renewal. The COS is for the 2nd time of holding the office of consulship.
Contrary to what you learned in school about "Roman numerals," actual Romans did not use IV for 4, but IIII.
Also, a legend signifying TR P without numerals would be the first time as Romans did not use a numeral to signify the first time in office. If you would like to bookmark a site explaining the abreviations on Roman Imperial coinage, this one is very good https://www.forumancientcoins.com/dougsmith/abb.html
Very scarce. The Romans generally used the additive principle. IV became the standard (subtractive notation) after the fall of the Empire. Also, and probably more important to Romans was the fact that IV is the first two letters of IVPITER (Jupiter), the main God, so not really appropriate to use it as a mere number. Names and titles were OK
In the MA Legionary series, the numeral "IIII" is very scarce if not rare, while "IV" is not scarce at all.
There were no strict rules for Roman numerals. On this gravestone of a centurion who died at the battle of Teutoburg against the Germans, his legion's number is written : LEG. XIIX. But other inscriptions may use the form XVIII like this one :
Here's Apollo relaxing with his lyre - a IIII (not IV) and a V. Interesting to see Gordian has a moustache and sideburns on the earlier one (IIII) but clean-shaven on the later (V) example. Maybe his mom made him spiffy up: