Siege coinage is generally crude, including this type, as they are put out in a hurry and under little or no quality control. I find this example interesting due to how extremely crude it is, even compared to what is generally seen for the siege coins of 1793. Aside from being misshapen, the edges have large caves. I am under the impression these coins were struck, but this one looks more like it's cast.
It surely is an interesting coin, Numismat. Maybe it is struck, but on a very poor quality, damaged planchet. Bruce
For obvious reasons, yes. That is pretty much the same fascis, with a Phrygian Cap at the top. http://www.horizonfr.com/les_cotations_ecus_sols_deniers/les_sols_siege_de_mayence.htm The piece is crude indeed, but as the OP wrote, it is an interesting historical document ... Christian