Wow...definitely a loaded question considering there are true old ones, ones that were used only as a form of currency all the way up into the 20th century, ones that were used as wedding doweries/gifts (to my understanding, these cheaper made pieces are like symbolic pieces, like a Victorian copy of earlier piece) and, of course, modern fakes. I know very little how to spot the fakes, but it is my understanding that the older ones were typically plainer than the more modern and currency models (lacking the dolphin and dragon decorations, etc). Likewise, the ones used as true firing pieces had their trunnions set low on the pieces so thay could be used as true swivel-type rail guns (meaning, I have seen some of the modern faux-verdigris guns with trunnions directly extending from their sides, thus, not true swivels as the lantankas were intended to be). Also adding to the confusion is that the larger of the pieces were true weapons whereas the smaller ones were just signallers. What length constituting which was a fighter and which wasn't hasn't been made clear to me in any of my research. Sorry if this causes more confusion than answers-
Look for true signs of wear and aging, including inside the barrel. Perhaps look up how the new ones are given fake green patina and how to spot it.
