[Clubs & Arrows]

Here's an odd Philippine shield that I just picked up yesterday. The Bagobo Shield is just shy of 39" tall x 13 3/4" across the top x 1/2" thick, and has repousse tin overlay work tacked/nailed over it's face instead of painted desin work. The green details on the back look like trade paint and not pigment. The wood has age to it and there is some darkening to the handle and in the cavity around it. The rear shows that the the two horizontal rattan or wooden strips were there at one point.
This being said, I don't know what to make of it, whether it's for dance or ceremonial use. Was it redressed at some point? Any ideas?