Nonoy Tan, you bring up a good point.  If I understand right, there are datus in those cultures.  I will see if I re-find past research upon which I base this.   
 
In addition I would add that these types are perhaps ceremonial, but I base that due to the nature and work of the materials covering the shafts.
		 
		
		
		
		
		
		
		
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