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					Originally Posted by df1967  Just the producer sign HF I really have no idea. | 
	
 I have no knowledge to speak of at all about canons but regarding the HF marking: 
this one looks relevant and fits with corrado26 suggestion that it may have been Scandinavian. The description:
	Quote:
	
	
		| A SMALL SWEDISH IRON CANNON, HÄLLEFORS FOUNDRY, 19TH CENTURY formed in five tapering stages divided by mouldings, plain trunnions with the letters ~HF~ in a rondel between, raised vent field and globose cascabel 28.3 cm; 11 1/8 in barrel 1.6 cm; 5/8 in bore Property from the David Jeffcoat Collection (1945-2020) Part proceeds to benefit The Wallace Collection Hällefors, west of Stockholm, was an important iron founding centre from the 17th century. | 
	
 (emphasis mine)
