Interesting Error

278, Lot: 399. Estimate $200. Sold for $700. This amount does not include the buyer’s fee.

Diocletian. As Senior Augustus, AD 305-311/2. Æ Follis (27mm, 9.76 g, 12h). Cyzicus mint, 6th officina. Struck AD 305-306. Laureate bust right, wearing imperial mantle, holding olive branch and mappa / Providentia standing right, receiving olive branch from Quies standing left, holding scepter; S-F/Kς//PTR. RIC VI 671 (Treveri). Good VF, brown patina with just a trace of silvering. One of the most unusual issues in the entire follis series.

This issue is nearly always attributed to Trier (Treveri), but a comparison of portrait styles and an examination of follis hoards reveals that it was struck in Cyzicus. Two officinae struck this issue, Δ and ς, and the Kς in the field between the two figures is the actual mark of the mint, not the PTR. A look at the coins of Cyzicus (RIC 22-23) shows that the same two officina also struck this issue without the PTR.

Why then the apparent double mintmark on this issue? It appears that the first coins of this type were prepared at Trier and examples were sent to the various mints for the for the purpose of copying. At Cyzicus, the die engravers copied everything, including the Trier mintmark, and placed their own mintmark in the field. Eventually someone realized the mistake and new dies were prepared with the mintmark in its proper location.