that is a FANTASTIC coin...super sharp details. looks like symmetry was important to these guys? i don't have many coins from the 9th century, here's the only one i have that is for sure, totally 9th century only. 813-820, leo v (and constantine v)...from the "frenemies" to the east, the byzantines.
Following are a few examples of Charlemagne's coinage. Not mine unfortunately Monnaies d'antan - auction 13 (16.05.2013) Charlemagne (768-814) - Denier (Bourges) A/ + CARLVS REX FR entre deux grénétis. Croix cantonnée de quatre croissants. R/ + BITVRICAS entre 2 grénétis. Monogramme de Carolus. RR SUP. Nou.85b-Dep.175 Ar ; 1.65 gr ; 20 mm Q
CGB - MONNAIES 58 (24.04.2013) CHARLEMAGNE Denier n.d. Melle R2 silver (17mm, 1,05g, 9h) Obverse : CARO/LVS en deux lignes Reverse : MEDOLVS autour d'une croisette Ref : G.94 p. 122 Prou.684 var. pl. 16 MG.268 N.44 p. 55 Q
Charlemagne, denier de Mayence, 1,60 grammes, Exemplaire, Cabinet des Médailles, BnF, Paris. Av: KAROLVS IMP AVG. Buste drapé, diadémé et lauré de Charlemagne à droite. Sous le buste, la lettre M. Rv: XPICTANIA RELIGIO. Temple surmonté d'une croix. Au centre du temple, une croix. Prou.- Q
And for those who wouldn't want to sell their house for acquiring one of the above, the Paris mint has edited in 2000 a 5 francs coin after the portrait denier of Charlemagne (part of a series of nine 5 francs coins celebrating "2000 years of coinage in France" or whatever the title is, you get the point) They're worth a mere 50 to 80 € in perfect condition, not very easy to find though, being only minted at 5250 examples Q