Illustrations of Sassanid Persian Clibanarii

[Dan Howard]

With that limited goal in mind the Arlon bas relief is relevant as it gives a precedent (even in Dan's restricted use of the term) for Roman use of plate-over-mail defences. In my opinion this strengthens the plate-over-mail scenario and weakens that of mail-and-plate.

I don't see any mail at all in that carving. Even the plate is tenuous. It could be interpreted several different ways. There is no way to tell without knowing how it was painted.