Denier - Charlemagne Mainz, monogram

Charlemagne's monetary reform of c. 793–794, enacted at the Council of Frankfurt, fundamentally restructured Frankish silver coinage — heavier blanks, tighter weight standards, and production concentrated at authorized royal mints. Mainz was among the most productive of these, sitting at a critical junction of Rhine trade routes. The monogram type belongs to this reformed series, not the earlier, lighter issues of the 768–793 period.

The Carolingian pound was redefined at roughly 408 grams, yielding 240 deniers — a ratio that persisted across Western Europe for centuries. This particular piece at 1.69g sits at the lower edge of the reformed standard, consistent with documented weight drift in later production runs from Mainz.