very interesting, ron! thanks.
i'm particularly intrigued by the tang's square to semi-round cross section, because this 10th to 15th century visayan kris which was discussed somewhat extensively here in the forum
already shows a square cross section (see illustration below).
on the other hand, i don't doubt the antiquity of the kris above.
but i'm no expert on krises. hence this visayan kris is being shown just for additional inputs ...