CENTRAL GAUL. Sequani. 1st century BC. Quinarius (Silver, 13 mm, 1.86 g, 6 h), two-sided brockage mint error. Q•DOCI Celticized head of Roma to left. Rev. [Q•]DOCI / SAM [F] Horse springing left. CCCBM II 346-65. DT 3245. LT 5405. A highly interesting mint error. Good very fine.
On some coins of this series, traces of a second obverse die are visible at the rim (cf. Leu Web Auction 40 (2026), 2250). This may indicate that multiple dies were used in striking, allowing several pieces to be produced simultaneously. The same seems to have occurred here, as the obverse is markedly off-centre. Even more remarkable, however, are the impressions of another coin visible on both sides - an extremely rare example of a double-sided brockage mint error