The T-F//PTR issue of Constantine the Great at Trier caused the writers of RIC some problems. The issue is split between RIC VI and RIC VII but there are more subtle splits even than that. RIC VI p. 225 shows us the "heavier follis" dated c.309 with coins in the weight range 7.0-5.0 gms. The issue contains two Mars types - MARTI PATRI CONSERVATORI (Mars standing right leaning on shield) and MARTI PATRI PROPVGNATORI (Mars advancing with spear and shield) and two PRINCIPI IVVENTVTIS types (whic I will ignore for brevity). RIC VI 829 - 843. RIC VI p. 226-227 shows us the "lighter follis" dated to 310-13 with coins in the weigth range 5.0-4.0 gms. The issue contains the GENIO POP ROM, MARTI CONSERVATORI and SOLI INVICTO COMITI types. RIC VI 844 - 876. At some point during the T-F//PTR issue there was a break between east and west in the empire and coins of Maximinus II Daia stop production. RIC VII p. 167-168 shows us the continuation of this "lighter follis" issue dating to 313-315. All the examples allocated to this issue seem to have been given R3-R5 scarcity wheras the RIC VI coins are all given C2 through to R scarcity. Some thought has been given to sub-dividing this issue into years based on weight. This is problematic too since hoard analysys cited in the notes seems to indicate that a weight range of 6.30-3.50 gms. It would appear that the coin are spread across the weight range without distinct groupings of weights that might indicate a sub-division by weight alone. RIC also places all coins almost all coins with the obverse legend IMP CONSTANTINVS P F AVG in the "earlier light issue" as these are generally realtively heavier. There seems to be problems at every turn with this issue. The issue was followed by the A-S//PTR issue. I have recently obtained a Mars example from the T-F and the A-S issue and thought it worth sharing them here to illustrate how some of this confusion might arise. Firstly the T-F Follis Obv:– IMP CONSTANTINVS P F AVG, Laureate cuirassed bust right Rev:- MARTI CON-SERVATORI, Mars helmeted, in military dress, spread cloak, standing, right, holding reversed spear, left hand leaning on shield Minted in Trier (T | F / PTR). A.D. 310 - 313 Reference(s) – RIC VI Trier 855 (rated S). 3.64g. 23.95 mm. 180 degrees And the A-S issue Follis Obv:– IMP CONSTANTINVS AVG, Laureate, cuirassed bust right Rev:–. MARTI CON-SERVATORI. Mars helmeted, in military dress, spread cloak, standing, right, holding reversed spear, left hand leaning on shield Minted in Trier (A | S / PTR). A.D. 315-316 Reference(s) – RIC VII Trier 80 (R2) 3.76g. 20.44 mm. 180 degrees My T-F coin is distinctly larger than the A-S coin but is lighter. Here they are together to aid comparison. We will probably never know but was the T-F issue broken into sub-issues or was there simply a much larger than usual weight distribution within the issue. Thoughts? BTW I was drawn to the pleasing details on Mars on both these. Martin
Somebody needs to do a study of T-F vs. S-A. (Somebody smarter than me, that is.) These field letters occurred in A.D. 307-309, too. S-A was first, A.D. 307-308: Treveri (Trier) mint, A.D. 307-308 RIC 772a Obv: IMP CONSTANTINVS P F AVG Rev: MARTI PATRI CONSERVATORI - Helmeted Mars, with shield and reversed spear PTR in exergue; S in left field, A in right 26 mm, 6.9 g. Treveri (Trier) mint, A.D. 307-308 RIC 776 Obv: IMP CONSTANTINVS P F AVG Rev: MARTI PATRI PROPVGNATORI - Helmeted Mars, with spear and shield PTR in exergue; S in left field, A in right 26 x 24 mm, 6.5 g. Followed by T-F in A.D. 309: Treveri (Trier) mint, A.D. 309 RIC 830 Obv: IMP CONSTANTINVS P F AVG Rev: MARTI PATRI CONSERVATORI - Mars, helmeted, nude, standing, facing right, holding reverse spear, resting shield on ground PTR in exergue; T in left field, F in right 25 mm, 7.6 g. Only to return again, as you noted, in A.D. 313-316: Treveri (Trier) mint, A.D. 313-315 RIC (v.7) 47 Obv: CONSTANTINVS P F AVG Rev: SOLI INVIC-TO COMITI - Sol, standing right, looking left, holding globe in left hand, right hand raised PTR in exergue; T in left field, F in right 19 mm, 3.4 g. Treveri (Trier) mint, A.D. 316 RIC 118 Obv: CONSTANTINVS P F AVG Rev: MARTI CONS-ERVATORI - Mars, helmeted, in military dress, standing right, looking left, holding spear and resting hand on shield. BTR in exergue; T in left field; F in right. 20 mm, 3.2 g. (I don't have any examples of coins with A-S field marks from this period.) So what is the significance of these letters? Why are they used for a few years, disappear for a while, and then return?
Hi, P. Bastien and H. Huvelin have well shown in "Trouvaille de folles constantiniens (307-317) Bastien-Huvelin -1969" that the essential data is not weight but dot circle (grènetis) diameter. 21mm belongs to pre-313 reform coinage and 19mm to post-313 reform coinage. Of course, they are respectively cut to 1/72 (~4.5g) and 1/96 (~3.4g) of a pound but these are average weights for 72 or 96 blanks cut in a pound of metal.
Interesting! And as per @Genio popvli romani's information, the ratio of 21:19 is just about exactly the ratio of the dotted border diameters measured on images of the two coins shown by Martin.
Your comment does not make it clear that you understand: the occasion for the break between RIC VI and VII is the death of Daia in 313. Keep in mind that Sutherland (VI) lists rarity for whole issues by mint (noting the officinae) but Bruun lists rarity for each officina. To compare the rarity numbers between the two you have to add the officina rarity numbers in VII together. Also important to recall that these two scholars, more assiduously than their predecessors, use the rarity figures to signal the distribution of a data set among the specific source collections they are using for their study. It is NOT a market study, but rather a study of a fixed population. No guarantee of any correlation to the general market, but a well defined control group that can be interpreted reliably by any competent observer. Replicable. Instead of flan size, compare the design size (measure the surrounding design circles border to border not edge to edge). By linear dimension note that the design of your "smaller" coin goes all the way to the edge, but the "larger" coin has edge beyond border. How do the design sizes compare? That will tell you more about what was intended, as opposed to what "happened."
This is a critical point and something one must keep in mind. After Diocletian's reform, and especially under the House of Constantine, the rule becomes flans per pound and not pound portions per coin. The flex allowed the coinage to take on more of a fiduciary aspect than a rigidly specie currency with tight weight standards. It was still a specie currency and would vary in mass with movements in inflation, but a coin was a follis (or whatever) because the government said it was, not because you could set your balance pans by it.
Exactly, it's a system based on confidence. And the volume of folles / nummi hoarded at this time shows that it was far from being acquired ... The bad currencies drive away the good ones.
