different weights, same value

[Heliodromus]

Here's a quick onboarding photo of two coins I received today, from same group find. Both coins were issued around 311AD, and were circulating (and lost/hidden !) together.

The Comiti AAvvgg, weighing 4.6g, was issued by Constantine (recognizing Maximinus Daia) at his prevailing weight standard of 1/72lb (4.51g). The Genio Avgvsti, weighing 6.9g, was issued by Licinius (recognizing Constantine) at his prevailing weight standard of 1/48lb (6.77g).

The differerence in weight between these is extremely obvious in hand, despite only being a couple of grams (but still one 50% heavier than the other). The diameters are about exactly the same (22/23mm), with the weight difference coming from the flan thickness which is again extremely obvious.

Despite the 50% difference in weight, as far as I'm aware both coins had the same purchasing value.

It's interesting that this 50% difference in weight doesn't appear to have been enough of a profit motive for contemporary counterfeiters to arbitrage, since unofficial copies of Western (here London) coins of this time are very rare (I can't even recall seeing any). However, a bit later in 318 when Constantine introduced a new 5% silver "centenionalis" denomination (VLPP/etc), this brought out the counterfeiters in droves!

Ben

[SC]

Indeed a bit of a mystery.

I agree that this does not seem to coincide with a high point of counterfeits.

Lots of changes going on over the next few years so perhaps the issue was addressed before large scale counterfeiting began.  But that is only a guess.

One wonders if situations like this would have led to coins' true values being based on weight, at least for some periods or situations.

SC

[Callimachus]

The difference in weights between your coins is due to inconsistent weight reductions at different mints.

From 305 to 313 the follis was reduced in weight at all the mints, but the rate of reduction was not the same from one area of the Empire to another. That was because no one emperor controlled all the mints. As RIC puts it:

“The disintegration of the tetrarchic system brought decentralized control of the coinage; and not until Constantine and Licinius reorganized the Roman world from 313 was some uniformity restored to the coinage.” (RIC, vol. VI, p. 93). 

Several pages later, RIC continues:

“The weight of the follis was sharply reduced on two occasions, as can be seen from the appended diagrams. The first reduction from the +/ - 10.00 gm. norm to one of 6.5 or 6.25, took place very early in 307 at London, Trier, and Lyons. This reduction was reflected by Maxentius almost immediately at Aquileia and Carthage and (after a short pause) at Rome: a longer interruption preceded the new standards at Ticinium.  . . . It would seem that reduction in the west and centre found mints elsewhere unprepared for a corresponding move. In 310 a second reduction, to a standard of c. 5.0 - 4.0 gm was introduced at Trier and London; the fall was echoed at Rome, though not to such an extent. Once more the reaction of mints elsewhere was delayed: it was not until 311 that their aes standards began to drop, often in an untidy ‘slide,’ and at Alexandria the real drop did not come until 312.  . . .  The aes picture as a whole between 307 and 313 is that of two reductions initiated by Constantine, quickly adopted by Maxentius but only hesitantly copied eastwards, where the standard tended to slide instead of being neatly and sharply dropped.”  (RIC, vol. VI, pp. 100-103).

Study the tables below for London and Siscia for the year 311, and you will see where your coins fit into the weight reduction scheme. You may have to click on the image to enlarge it.

(By the way, for those only interested in getting an RIC number, the introductory material to each RIC volume and the introductory essay to each separate emperor and/or mint in each RIC volume, contains a lot of very interesting information.)

[Heliodromus]

Yes, I was aware of the different prevailing weight standards (which I note in my post), although it's easy to forget these when handling coins of this period individually; the impetus for my post was happening to have these two coins - minted at same date -  in hand at the same time, when the difference invokes quite a visceral response !

I have to admit that I don't think I've ever read that section of RIC...  it's too bad that they present this so clearly here, but then have the all-but-useless (given loose weight control in practice) min/max specimen weights throughout the body of the text, rather than just referring to the nominal weight standard. I'm not sure why RIC doesn't present the weight standards at the mints east of Siscia in this same nice format (maybe it's there someplace else?), as there are interesting dislocations there too, with Maximinus Daia's mints only aligning with the rest after coming under Licinius's control.

My post was really meant more as a commentary on the equal value (given the differing weight standards) than the weights themselves. I guess it's basically a reflection on the fiat nature of the bronze coinage at this time, exacerbated by the soaring inflation that devalued bronze relative to silver and gold. In 311 a counterfeiter *could* have melted Licinius's coins and created Constantinian counterfeits out of them in 2:3 ratio, but evidentially the material cost of bronze wasn't the deciding factor and the potential for worthwhile profit wasn't there.

It's interesting that the slightly higher silver content (4-5%) after Constantine's coinage reform in 318 was enough (assuming it was the driving factor) to suddenly make counterfeiting profitable/common. Constantius II passed laws against illegal melting of the bronze/billion coinage to extract silver, so apparently there was even a time when the minimal silver content in the coins was worth more than their face value (similar to our time when all the old UK/US silver based coins have headed for the melting pot).

From a counterfeiter's perspective the cost of making the debased coinage of 311 or slightly enriched ones of 318 would have been the same given that they'd be using 100% bronze in either case, so the fact this was only widespread in 318 would seem to attest to a higher face value of the the coins at that time. I'm not sure why the VLPP (initial post-reform type of 318) was so much more heavily counterfeited than subsequent issues... maybe a reflection of continued rapid devaluation of the currency and perhaps law enforcement catching up with the new practice ?!

Ben