Many thanks, Joerg for your opinion.
I searched for a forum specialized in knives, but, it seems to me, they mostly talk about hunting knives or daggers, rather than table knives.
I have a very good book on cutlery :" Historiche Bestecke".
Among the blade marks in this book there is one that closely resembles the one on the blade of my knife, but I don't have enough experience to tell whether it is exactly the same mark or just a resemblance.
Everything would lead to dating the knife to the late seventeenth, but it seems too good to be true.
I'll keep researching to be sure.
Best
Amena