Hi all, interesting thread..
Here's a book which might be useful, "Ukkil: Visual Arts of the Sulu Archipelago", by Ligaya Fernando-Amilbangsa. Chapters of interest.. Chapter I - Decorative Motifs and Symbols; Chapter VII - Blacksmithing and Casting; Chapter VIII - Goldsmithing and Silversmithing.
For more details, see here:
http://alamshah67.multiply.com/reviews/item/113