Interesting thing! I've had a very similar one years ago, also with a similar marking and the same closed curl on the dorsal quillon. 
 
I bought it when I was living in Beijing, the collector who sold it to me said it were Guomintang military markings, but I've never been able to verify this. 
 
See attached a picture of the one I had.
		 
		
		
		
			
		
		
		
		
		
		
		
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