Not sure if this is a recent change or not, but a decent portion of the
Paris BnF collection is now online.
This seems to be a work-in-progress since currently for
the tetrarchy it seems to be fairly
complete, but for
Constantine so far it only includes the bronze medallions.
You can
search the
collection here:
https://catalogue.bnf.fr/index.do1) Enter
search term using
french version of emperor's name (e.g. "constantin" for
Constantine) and hit ENTER
2) On left
side of screen go to "Nature de document" section, click (+) to expand it, then select "Objects monetiformes" (i..e coins)
3) On the next screen you can further refine your
search using sections on left
side of screen, e.g. in "
Collections" select "serie romaine"
4) Click on image in
search results to view item details
5) On individual coin screen, click on "Consulter en ligne" at screen bottom right to see both sides of coin
Ben