I feel too that it's a Phil. piece, for reasons already mentioned. As to the lack of Katipunan markings, I'm guessing that perhaps it's because it was made before or after those tumultuous years (i.e., 1896-1898 Phil. Revolution, and 1899-1902 Phil.-American War).
This beautiful piece reminds of
the one that got away (sample pics are below, for convenience) ... sorry to remind you, Dimasalang!
On the 'x' over the diamond motif on the ferrule, am not too sure but I think I've seen that in some old Phil. potteries. I've leafed through some of my books but can't find where I saw that design. But I'm no expert on potteries. Maybe Nacho can comment if he sees this thread ...