Sometimes the smallest detail can make the difference in an attribution. The following coin type comes from both officina 3 and 4 at Lugdunum marked with either C or D. Officina 3 regularly also make their mintmark retrograde. Now the difference between a D and a retrograde C is quite small but you can see enough detail on this coin to see that it is indeed a retrograde C rather than a D. Now that's what I call minutiae! Maximianus - Antoninianus Obv:– IMP C VAL MAXIMIANVS P F AVG, Radiate, draped and cuirassed bust right Rev:– VIRTVS AVGG, Hercules, standing right, leaning on club, with lion’s skin on rock. Minted in Lugdunum (Retrograde C|_). Emission 5. Officina 4. Autumn A.D. 287 – Autumn A.D. 289 Reference:– Cohen 565 Bastien 65 (2 examples cited). RIC V Pt. 2 Lugdunum 437 Weight 3.93g. 22.64mm. 180 degrees
Neat find! I'd say that's a reasonable difference. Unlike buying a coin based on the position of of an arm
