Actually there are several grades of bronze. There is Manganese and Leaded Manganese Bronze(C86100-C8680), Silicon Bronze(C87200-C87900), Tin Bronze (C90200-C91700), Leaded Tin Bronze (C92200-C92900), High-Leaded Tin Bronze (C93200-C94500), Nickel-Tin Bronze (C94700-C94800)and Aluminum Bronze (C95200-C95800). As well there are many brasses which some of actually have a higher resistance to corrosion then some bronze.
Guess which bronze canons were made from?

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