Very interesting. My wife was an ethnomusicologist and we got permission to make casts of a purported Javanese kulintong owned by an Ivy League university. We removed the accumulated hand oil and grime in preparation to cast and discovered welding lines! These bronze gongs had been sold to the university as mid 19th century when in fact the technology used was not available until World War Two and only in shipyards in the Philippines. That dated them from after the Philippines had American shipyards near the end of the war. They did not want to know they got scammed.