Your vase may certainly be Polish, but that it not Jablonski's initials or name on the bottom (he always signed his pieces very neatly with a Polish-type 'AJ' or 'Jablonski' or 'A. Jablonski').
Quite a few pieces seem to be popping up (which do certainly look like Jablonski's designs, or later, Marian Pyrcak's designs) but they've got a FiC or F&C scratched onto the bottom (like yours). I don't know who or what FiC or F&C was/is... perhaps an importer or distributor?
At any rate, that is not Jablosnki's mark on the bottom though the piece may be his design. "F&C" remains a mystery for the time being.