I would expect it came to the area via Arab Traders. 
I don't believe any ivory product comes from Rhino; just horn. 
Hippo ivory often shows a line of tiny black dots at one place on the surface of the tooth. 
There is also Dugong ivory that would have been available locally; but the animal has been extinct for quite some time.
		 
		
		
		
		
		
		
		
	 |