Weights, Diameters and Composition of Ancient Coins

[Joe Sermarini]

There isn't any one place to find the weight, diameter and composition of all the various types of ancient coins.  These facts are often buried throughout references.  When you come across this type of information, please post it here.  

[Robert_Brenchley]

I've just got a copy on an ANS book, 'Chemical Composition of Parthian Coins', Earle R. Caley, 1955. There's far too much info in there to ry to post it all, I might post some of the most important bits. Meanwhile if anyone's got any queries, ask away.

[Rugser]

Throw a rule of weights out and measures in the Roman coins are a job "improbus".
From the observation of thoudands of Roman had coins materially in the hand I could tell that their weight and measure is much varied also during the same emperor. They exist As of Marcus Aurelius of weight, any times, inferior at 1/ 2 between them.

The chart that I insert is a small example.  

http://www.uniroma2.it/eventi/monete/nocpan.html

ser

[Simon]

DOC does list size and weight for each variation of a particular  Byzantine coin.

[Jochen]

Hi!

This I got via NUMIS-L:

I've pull Harl's Coinage in the Roman Economy 300 B.C. to A.D. 700 (Johns Hopkins University Press, 1996) and found the following for you:
 
p. 75:  "The purity of the denarius, which had fallen as low as 92 percent fine in the latter days of the Republic, was restored to its traditional level of 975 to 98 percent fine [under Augustus]..." 
 
p. 74: "Augustus issued virtually pure aurei and denarri struct at the respective standards of 40 and 84 to the Roman pound."
 
p. 90:  "Titus slightly improved the fineness of the denarius...In 64 Nero --- under the pressure of debts incurred in a desultory war in Armenia, rebuilding Rome after the Great Fire, and his own depraved extravagance --- conducted the first major debasement since the Second Punic War..."
 
p. 235:  "Nero...debased the denarius by more than 20 percent.  Its weight was reduced by one-eighth from 84 to 96 to the pound and its fineness was lowered from 98 to 93 percent...Furthermore, many denarii were deliberately struck below standard so that actual debasement probably ranged upwards to 25 percent or more."
 
p. 127 also has a chart of weights and fineness of denarii from Antoninus Pius (148-161) to Gordien III (241).
 
I hope this is helpful.
 
Cordially,
 
Kenneth L. Friedman

Best regards

[Lloyd Taylor]

There isn't any one place to find the weight, diameter and composition of all the various types of ancient coins.  These facts are often buried throughout references.  When you come across this type of information, please post it here.  

You might be interested in the following plot, which elegantly summarizes a couple of centuries of debasement of the Denarius. 

(Source: Popular Delusions When to Sell Gold by Dylan Grice - Societe Generale Cross Asset Research Strategy Document 23 March 2010)

[Kevin D]

Michael H. Crawford  ‘Coinage And Money Under The Roman Republic’  (1985)
Page 335, App. C  The silver content of coins of Magna Graecia (p. 33).

[chlorsilber (silver chloride, ‘horn silver’)]

                                     Silver          Chlorsilber           Copper           Lead         Reference
Neapolis      ?                87.55           5.77                    ?                     ?                (1)
Neapolis  Didrachm       91.63           trace                   7.13               0.88            (2)
Neapolis  Didrachm       93.02            -                         5.77               1.09            (2)
Neapolis  Didrachm       92.55            -                         6.02               1.22            (2)
Velia            ?                85.37           8.48                     ?                    ?                 (1)
Thurium   Diobol            91.09           trace                   7.15               trace           (2)
Thurium   Diobol            92.00            -                         7.03               0.73            (2)
Heraclea      ?                76.27          13.04                   ?                    ?                 (1)
Heraclea   Diobol           94.14            -                         5.58               0.10           (2)
Tarentum  Obol              88.45           some                 10.19              0.51           (2)
 
References:
(1) GGA 1843, 2, 1289.
(2) E. Bibra, 'Uber alte Eisen- und Silberfunde (Nürnberg and Leipzig, 1873).

[Henry S]

Got a chance to XRF a Philip II AV Stater and a Alexander III AV Stater (Teos, ca. 310-301 BC, Price -; Hersh-; Arena 16, pl. 13, 30.)

The Philip Stater was 99.82% gold, .09% Silver, and .07% Copper, with a trace of selenium.

The Alexander Stater was 99.5% gold, .25% silver, .14% copper, and .1% selenium.