I have had a few razor came my way with initials roughly carved on them like that.
Maybe the owner name was Xavier.
Or maybe he just wanted to mark it for differentiation, being with other guys in a confined space, like army barracks or something.
I guess I'll have to settle for X marks the treasure spot :-/ lol
Here are some pictures of 2 others, plus a full picture of the one I first posted. One is a french razor (Ferrière), another is a Sheffield (Wade&Wingfield) and the other one is the ivory scales I recently got on the BST from France (they are in a zipplock with some mineral oil, I tried to process the shot to show the X mark as well as possible).