The mingling of the helms

[jho]

Is that a hard dating Jens? Or could the helmet have been dug into an older layer? Helmets like these were almost always gilded or silvered and we often find them because they were hidden as items of value.

The excavator reports in Klumbach, Spätrömische Gardehelme, that he was present when the helmet was found near a wall in the topmost destruction layer of insula 20. He preferred to associate the helmet with a later phase and claimed that, as it was the topmost layer, there was a possibility that the helmet could have been dug into the older layer. This was, however, apparently based more on the fact that he could not believe that this type of helmet was in use earlier than the 4th century AD than on any real factual indication that the layers had been disturbed.

Many militaria were found in the civilan city of Augst which are associated with fighting in the city area in the 270s AD. However, as you correctly observe, deposition of this helmet would not appear to be a direct consequence of battle because, although no traces of silver sheet were found, all rivets had been removed before it was deposited. Whether this means that it still belonged to the battle but was stripped and deposited afterwards or whether it is more likely to have been independently deposited at a much later date, I cannot say. There appears to be little indication of use of this area beyond the 270s AD, but a deserted ruin may also be a good place to hide a helmet for whatever reason.

Do you mean a Berkasovo nose guard/nasal?

Yes, exactly. The find was discussed on RAT some time ago.