Hello Jim,
thank you very much for your expert comments
thanks for the link to Wallace A486, I also found a similar in the estruch collection. Iam still not sure if this mark is a splitted cross (like missaglias)
or a early ORB representing a church or a crossed heart
The cross mark with a square at the center are found on 9th and 10thC Viking swords in Finland.
So my search did not make any sense at all
Best regards from Holland