If I am not mistaken, there is a parallel in wootz in India (according to some folks like Jens) where the good wootz were only afforded by the higher elite and the pattern welded were reserved for those a little below that.
By the way, here is one of my twist cores only on a Bagobo piece in this thread (need to scroll down to see the faint twistcore:
http://www.vikingsword.com/vb/showth...obo+twist+core
Could this have belonged to a Bagobo datu?