Armatura della Colchide

[Luca]

On the off-chance that it isn't a modern fake, it could be part of a triumphal monument as suggested above, or a non-Roman imitation of Roman regalia. Even the Sutton Hoo regalia was a late barbarian imitation of Roman gear.

Good points. If the armor is original (which I too doubt) maybe it isn't really Roman. It could be Armenian. Armenians were partially Romanised and their cavalry too, IIRC, wore face masks as did some Persian cavalry. Brass may have been good enough for an Armenian king or officer, who knows. (Just wild speculation )

I agree with both. The higher probability is that is an "ancient" fake, could be done in Middle Age or during XVII-XVIII centuries. This could explain the mixture of symbology and different artistic touches comparing the classical roman art.