As Fernando remarked earlier in this thread, the image of what I thought was the typical Hernandes punzone was very poor (vendor) and I saw what I wanted to see.
I approached the ricasso inside the dish with some white spirit, as I have found most black discoloration is old preserving oils or waxes - or both - and a lot of the muck did indeed come off; enough to indicate there was no marking beneath it.
The mark I posted earlier today is from the lower end of the fuller (on both sides). I have seen quite a few that are similar, but not one that is an exact match (see pics). That, along with the name, is the only indication of provenance.
ps
I will comment once again on the peculiarity of the Es in the script (example top pic). I have seen them on several swords. They are embellished and flamboyant to the point of obscuring the meaning; this is despite all the other letters being relatively normal (by English standards - I hasten to add
).