Denarius, type 1, var 2 (CARLVS RX FR . monogram Karolus)

Obverse

Obverse legend

Reverse legend

Reverse

CARLVS RX FR (circular legend around a cross surrounded by a circle made up of dots, a cross between FR and CARLVS)

AGINNO (circular legend around the Karolus monogram (1) surrounded by a circle made up of dots, a cross between the letters O and A).

One copy preserved at the Münzkabinett der Staatlichen Museen of Berlin, link to the page of their website showing the photo of the coin: http://www.smb-digital.de/eMuseumPlus?service=ExternalInterface&module=collection&objectId=2448449&viewType=detailView. 

Monograms Karolus:

(1) Without letter A in the diamond on the middle.

(2) With the letter A inscribed at the top in the diamond on the middle.

(3) With the letter A written at the left in the diamond on the middle.

Another the copy preserved at the Bibliothèque Nationale de France (public domain), link to the page of their website showing the photo of the coin: https://gallica.bnf.fr/ark:/12148/btv1b104424849.r=charlemagne%20denier?rk=493564;4.

Yet another copy sold by OGN numismatique, link to the sale and their website: https://www.ogn-numismatique.com/article.asp?langue=fr&article=2304.

The only difference between type 1 and type 2 is in the legend REX FR for type 2 instead of RX FR (type 1) and the monogram Karolus instead of Carolus (type 1). Variants of type 2 only locate in the position or absence of the letter A in the monogram. Which I chose to note as a variant, even if this detail is tiny. It is never useless to note everything.