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.

Well, in the case of these conus ornaments I don't see it as a fraud or fake. It's just applying material that's available in the moment. It shows how flexible people are.

I agree with you Hans. The form is sometimes more important, than the material. Same with the Talhakimts from Westafrica. So many different materials were used for them. The significance for the users did not depend on the used material.
Attached are metal versions from this type of Mauritanian shell ornaments.

Since I cannot find the dialogue wherein I discussed this, I suppose it was posted at the previous BCN platform (bcn.com). Jamey

I handled a plastic one at one time - a cool discovery - It may still be in the Tasart collection.

Maybe you saw the one made of plastic, Joyce, that I sent to Thomas some years ago...

It´s the one at 12 on top that is made from a bottle cap...

Actually the one I was thinking of was from the James Lankton collection, and the only plastic one that I have seen. Fun discovery! I wonder how many plastic ones Thomas has now.:)