Very nice kris. Very well crafted and a good deal of the inlay intact. I would say it is late 19th century.
I'm not sure that "sundang" is the proper name for this weapon in Moroland. But i have been led to believe that half wavy blades like this are called Luma (Maguindanao tribe), Ranti (Maranao tribe) or Kalis Taluseko (Tausug tribe). Kris seems to be a good catch-all for these blades whether straight or wavy. Apparently the Maranao tribe do use the term sundang to refer to straight kris. The word sundang also seems to be the popular term for the Malay counterpart of the Moro kris.
Maybe others have more or different information on this name game.
