To my understanding, the arcing is caused by hard edges. E.g. all the elections could be at the end of a fork's tines, and EM field forces them to jump to another tine instead of going through the root of the fork.

Since spoons are rounded, they don't need to jump. I don't think the material plays much of a role in arcing other than providing resistance. They would heat up, but they'd melt before they arc. Still, they can arc from one spoon to another spoon when there multiple spoons close enough.

I'm lazy and don't use tik tok, but from what I've seen when my spouse is on there this would make an interesting tik tok channel (is that what they are called?). Spoon Spark, where someone collects a shit ton of spoons and people take their guess on whether or not they'll spark or even start a fire. Maybe get different power levels of microwaves to increase to throughout the tournament.

The E-Waste Arc Spark competition.

Yeah I know it uses waves towards the center but they are throughout the microwave, yet people don't questions the holes in the metal siding, which are metal circles. So if arcing was an issue on smooth sutfaces, it should happen there as well.

Yep, I have microwaved plenty of tea and coffee with the spoon in it.

You mean like a spoon on a glass or ceramic plate? That seems unlikely.

There is even companies that make glass/stainless steel lids for their microwave safe containers. So the lids won't warp like the plastic ones do and have to be thrown away

Oh definitely. Individual metal smooth ball, fine. 10 of them not touching fine. 9 spoons not touching, fine. But if one touches the wall of the microwave or another of the objects there will be a quick spark, and depending on how long the contact, maybe a flame+

Caveman posted a video below that basically shows without rough edges, your usually okay https://lemmy.world/comment/18066606

Note, stainless steel and glass lids are made for microwave safe containers.