Here is a call I recently sold on ebay. It is Myrtlewood Burl with a brass outer and glass inner and a Sweetgum striker. Sounds similar to copper but with a bit deeper pitch and real raspy. 
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				I do like that pot call.
			
			
			
				pretty neat
			
			
			
				Sweet looking call!
			
			
			
				Pretty call!
			
			
			
				That looks really nice...I have to say though I've never heard a brass pot before
			
			
			
				Nice 
			
			
			
				Great work & very unique piece of wood there
			
			
			
				very cool
			
			
			
				nice call