Coins from the Sacred Spring

New display - Roman Baths, King's Bath Corridor

The redisplay of a timeline showing Roman coins found in the Sacred Spring has prompted a lot of coin-related questions from visitors, with most people wanting to know why the coins of some emperors outnumber those of others so greatly. In modern Britain, where we are used to the same face appearing on all the coins all of the time, this is an idea that might take some explaining! Lots of factors to do with the coins themselves and how people used them go into explaining why the number of surviving coins from emperor to emperor can vary so greatly. First off, the really obvious answer: some emperors had really long reigns, so it stands to reason that their coins are going to outnumber those of other emperors who ruled for a shorter period of time! For example: Hadrian’s 20 year reign meant that the overall amount of coins he issued dwarfed the number issued by other less long-lived emperors. With that in mind, it makes sense that the number of surviving Hadrianic coins is so great in proportion to some other emperors.


But we shouldn’t think that emperor x will be well represented in museum collections and archaeological finds just because he minted lots of coins. One good explanation could be that some emperors’ coins were more debased than those issued by their predecessors, which reduced their value. What does this mean? It means that when an emperor found himself strapped for cash, he would order that base metal be added to the precious metal used to mint the coins. This is exactly what Claudius (of I, Claudius fame) did when he found himself short of silver. By diluting the precious metal mixture with iron and bronze, he could produce more coins from technically the same amount of metal. Geddit? It’s a little like how the gin lasts longer when you dilute it with tonic water, but with far less tasty and appealing results. Over his 13 year reign, Claudius’ mints churned out these debased coins possibly in their millions – and the Romans weren’t impressed! What seems to have happened is many people stashed away older less debased coins of previous emperors but continued to use the new Claudian ones for day to day stuff. The result was that the older more valuable coins had an increased chance of survival, while the Claudian ones got lost, broken, or were chucked into the melting pot. It is also probable that Nero (the next emperor) systematically withdrew and melted down Claudius’ less valuable coins to make sure that people did not continue to pull the nicer coins out of circulation and into their savings. This is why Claudius is very underrepresented in terms of coins, despite reigning for the same amount of time as Nero (whose coins survive in abundance).

Also, we can’t forget that the supply of coins to different parts of the empire was sporadic and fluctuating. Let’s take Britain as an example. Immediately following the conquest of the island in the 40s AD, the supply of coins from the continent is thought to have been minimal and intermittent, but picked up by the middle to late 100s AD. What does this mean? Well, it means that while Nero minted extensively throughout his entire reign, we are less likely to find him represented in coins from a British site because his reign comes so early on in the history of Roman Britain. On the other side of the coin (pardon the pun!), coins of Antoninus Pius and Hadrian appear on many British sites in greater numbers than Nero or earlier emperors who minted just as extensively. The reasons for such inconsistent supply are varied – war and conflict could disrupt the reliability of supply lines, and the demand for coins in a specific place may have had a large part to play in whether coins were shipped there in great numbers.

I hope that makes the issue a little clearer! The reason that some emperors have more surviving coins than others is more complicated than whether they minted lots or not!

Matt