Inflation for the moment seems to be relaxing a bit, the price of gas, one of the more daily visible symbols, was $3.30 a gallon yesterday at a gas station near me, a big improvement from last summer when they spiked up to about $5. This, along with an article by Kevin Butcher, triggered thoughts about inflation, monetary policy, and politics. Admittedly this note wanders from anything directly relevant to ancient coins and into a sidetrack with wishful thinking for modern politics.
My primary collection consists of Roman denarii, there Roman republican coins from the 2nd and 1st century BC are mostly high grade silver and weigh about 4.0g.
Roman Republican, C. Cassius, 126 BC, AR denarius, Rome mint, 3.84g
Obv: Helmeted head of Roma right; to left, mark of value above voting urn
Rev: C CASSI, Libertas, holding vindicta and pileus, driving quadriga right, ROMA in exergue
Ref: Crawford 266/1; Sydenham 502; Cassia 1; RBW 1075
Notes: for more on this coin see Cassius, Conspirator
Silver coins in the Roman Imperial period ranged from nearly pure silver (>95%) to barely any silver (<5%) as the coinage evolved from first to third centuries AD - the average weight of coins also changed.
Butcher, Kevin (2015) provides an interesting overview of the evolution of thinking about debasement of Roman coins in the 3rd century and especially with the introduction of the "Antoninuanus" by Caracalla. He at least seeds doubt about the easiest interpretation: linking debasement to inflation and currency collapse. He also notes the risk of contemporary context influencing our understanding of the past - a risk that I step into fully before the end of this note.
"In this essay I have not ventured to furnish yet another opinion about the consequences of debasement, or on the value of the antoninianus. That was not the point of the exercise. Instead I have tried to give an account of the development of thoughts about the third century debasements."
-Kevin Butcher, 2015There are open questions about the relationship between metal content and value. There are reasons other than inflation for why metal content of the coins changed over time e.g. profit for the state, as well as drivers of inflation other than lower metal content of coins e.g. greater abundance of coins. A sentence from the article that is worth keeping in view: "If there was high inflation in the period from 215 to 260, the Romans seem to have been uninterested in recording it. Hard evidence, in the form of price data, does not match the period of debasement."
The reduced use of silver in Roman coins over time is easy to see in hand if we look between the extremes of Augustus (reign: 16-Jan-27 BC to 19-Aug-14 AD) and Gallienus (reign AD September 253 – September 268).
First Century AD: a good silver coin (>95% silver) of Augustus (3.86g)
Second Century AD: A denarius of Antoninus Pius who reigned 11-July-138 to 7-March-161 still appears to be good silver content (a bit lighter @ 3.52g and roughly 80% silver).
Third Century AD: a 3rd century silver coin from Gallienus (reign AD September 253 – September 268). The so-called "double denarius" or "Antoninianus" often shows little visible silver content.
Gallienus
Looks can be deceiving, however, as this next coin may give the illusion of being higher quality silver - however in hand feels light and unconvincing as a silver coin and contains other light colored metals.
Gallienus, AD 253-268, AR Antoninianus, Colonia Agrippinensis (Cologne) mint, 1st emission, AD 257-258 (Joint Reign)
Obv: Radiate and cuirassed bust right
Rev: IOVI VICTORI, Jupiter, holding Victory and scepter, standing facing, head left, on cippus (small low pillar) inscribed IMP/C E S (IMPerator Cum Exercitu Suo) in two lines
Ref: RIC V 21
If there is a thin layer of silver on a 3rd century coin, it may be worn off from use of the coin or from time sitting in the ground, or it may be present but turned dark (silver sulfides).
Aurelian (AD 270 to 275)
Probus (AD 276 to 282)
Timing: Here's a graph of the table in Harl (Ch. 6 - The Great Debasement and Reform A.D. 193-305 Table 6.2 p 130)
Here is another graph from G. C. Haines 1941 illustrating data from J. Hammer (1908) the decline in silver content over time - more recent studies and techniques for analyzing the silver content may have improved on this view. The jump to 95% at the end of the graph representing the introduction of the Argenteus.
Although the argenteus was introduced by Diocletian in his money reform of 294 AD, it was not really a return to silver denarii - and silver washed coins were the more common currency. This large 26mm, 11.31g coin showing only a hint of silver at the surface was the intended replacement for the Antoninianus.
Diocletian, BI Nummus, Heraclea, AD 296-297, 11.31g
Obv: IMP C C VAL DIOCLETIANVS P F AVG, laureate head right
Rev: GENIO POPVLI ROMANI, Genius standing left, modius on head, naked but for chlamys over left shoulder, holding patera from which liquid flows, and cornucopiae; HTΔ in exergue
Ref: RIC Diocletian Heraclea 17a
In Diocletians reform the argenteus (a coin of high silver content) and aureus (gold) played only a "subsidiary role" (See: Coinage and the Economy, Kenneth W. Harl, 1996, p.141)
Galerius, as Caesar, AD 293-305, AR Argenteus, Rome mint, struck circa AD 294
Obv: MAXIMIANUS CAES, laureate head right
Rev: VIRTVS MILITVM, Diocletian, Maximian, Constantius Chlorus, and Galerius, draped, sacrificing over tripod; behind, gate in a six-turreted enclosure
Ref: RIC VI 29b (R2)
Here is a prettier graph of the debasement with a less clear source of data.
Another visualization of currency in the Roman empire can be found at this link:
This page reinforces the link to hyperinflation and collapse that Butcher tries to tone down.
How were plated coins made in ancient times? There were multiple processes potentially used to make plated counterfeit and official coins throughout time. While there are several candidates for silver plating in ancient Rome, there is uncertainty about the process used for late Roman coins. Here are several candidates (there are others mentioned in the references below):
"diffusion bonding" or "Sheffield plating" : silver copper sheets heated together reported in use for Roman Republican fourrée denarii, wrap copper flan in a silver foil and heat. This is considered too labor intensive to have been used at scale in late roman empire
"dipping in silver chloride" - Blanks were maintained hot, dipped in molten silver chlorides, and quenched in a bath
"mercury silvering", "amalgam plating", or "fire gilding" - a good way to get mercury poisoning - dissolve silver in mercury, then spread on the flan like peanut butter, then evaporate the mercury with heat, this technique is mentioned as a possibility for late roman coins.
"depletion silvering", "pickling" or "blanching" - take a copper-silver alloy - use citric acid or vinegar to leach out the copper and enrich silver content of the outer surface, then strike to produce a silver surface plating which seems to be a leading hypothesis for later Roman coins.
Ancient technology was a surprisingly sophisticated and included ploughs, irrigation, wheels, textiles, aqueducts, writing, ships, complex construction, and most relevant for this discussion: metallurgy of gold, silver, copper, and bronze. Bolos of Mendez in the second century BC describes methods for producing false silver:
"About the making of “uncoined”: the quicksilver from arsenic, or sandarach, as you prefer, cook it as usual, deposit it on copper or coppered iron, and it will be whitened. Whitened magnesia does the same thing, and transmuted arsenic, and cooked cadmia (ZnO?], and unfired sandarach and whitened pyrite, and psimuthion [lead acetate] cooked with sulfur."Giving in to tendency to make parallels between ancient Rome and the current environment, this graph of the decline in purchasing power of the US dollar is intriguing: is there a parallel between the debasement of currency in Rome and the loss of buying power in the US? Will congressional leaders who's primary objective seems to be "shut down the US government" to win political points, despoil US institutions and usher in a period like that which followed the end of the Roman Empire?
Decline in currency leads to inflation leads to lack of trust in institutions - is this too simplistic an explanation? Certainly the metal content of coins is not the same as the value of coins, nevertheless, perhaps it is fair to conclude that a bit of thoughtfulness in leading a country through periods of inflation is a good choice. A couple of George Bernard Shaw quotes that are often combined, strike me as both inspiring and a form of advice and admonishment to the "feverish selfish little clods of ailments & grievances" that seem to be having a moment of political empowerment in recent years.
George Bernard Shaw (1856-1950), His Life and Works, an authorized biography by Archibald Henderson, 1911
"This is the true joy in life, the being used for a purpose recognized by yourself as a mighty one; the being thoroughly worn out before you are thrown on the scrap heap; the being a force of Nature instead of a feverish selfish little clod of ailments and grievances complaining that the world will not devote itself to making you happy.
- George Bernard Shaw (1856-1950), Epistle from Man & Superman, 1903As always, constructive comments and discussion are welcome and appreciated.
References in addition to those linked inline and for further reading:
Butcher, Kevin (2015) Debasement and the decline of Rome. In: Bland, Roger and Calomino, Dario, (eds.) Studies in ancient coinage in honor of Andrew Burnett. London: SPINK, pp. 181-205. ISBN 9781907427572
Harl, K. W. (1996). Coinage in the Roman economy, 300 B.C. to A.D. 700. Baltimore: Johns Hopkins University Press
Haines, G. C. (1941). THE DECLINE AND FALL OF THE MONETARY SYSTEM OF AUGUSTUS. The Numismatic Chronicle and Journal of the Royal Numismatic Society, 1(1/2), 17-47
Susan La Niece (1990) Silver Plating on Copper, Bronze and Brass. The Antiquaries Journal, 70(1), 102-114. doi:10.1017/S0003581500070335
Cope, L. H. , (1974) “The metallurgical development of the Roman Imperial coinage during the first five centuries A.D.”, PhD Thesis, Liverpool Polytechnic, Liverpool John Moores University. doi:10.24377/LJMU.t.00005590
C. Vlachou, J.G. McDonnell, R.C. Janaway (2002) Experimental investigation of silvering in late Roman coinage, Mat. Res. Soc. Symp. Proc. Vol. 712
Pliny describes a technique for plating in Naturalis Historia book 34 ch. 48.
Keyser, P. (1995). GRECO-ROMAN ALCHEMY AND COINS OF IMITATION SILVER. American Journal of Numismatics (1989-), 7/8, 209-234
Forbes, R. J. (1953). On the Origin of Alchemy. Chymia, 4, 1–11
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