Best Antique Ceremonial Mask

Authentic antique ceremonial mask. Seems to be two birds at the top of the face, and some type of cat at the bottom. Incredible detail. I don't know what tribe or even what country it's from. It is signed (engraved) on the back, but I don't know what language. I'm pretty sure it is teak wood and best you can tell it's old. It is not stained and polyurethaned like reproductions. Beautiful piece ! It measures 13 1/4" x 6 1/4".