Hi GroxaB.
Yes, Philippines is the origin of this one, and it is most likely from central Luzon. The shape of the blade is very similar to the Negrito
hundang which also has the tang arising at the spine of the blade. You can find discussion and see an example of a
hundang here
http://www.vikingsword.com/vb/showpo...7&postcount=18
The grip is a typical Tagalog style, with full length tang, and the wooden core would once have had twisted wire (iron or brass) in the grooves.
Like Sajen, first half of 20th C. would be my guess.
Nice knife.
Ian.