Denarius, type 1, var 6
CARo _ LVS (inscribed in two lines).
CLS (the letters C and L under a tilde, a small horizontal line to the left of the letter C with a globule above and another below this line; a cross between the two bars of the letter C).
Photo of 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/btv1b10413750t.r=charlemagne%20denier?rk=321890;0.
|N°||G||F||XF 40||AU 58||MS 63||MS 65|
Seems never to have gone on sale.