If they really believe they have the only sample they won't let it out of their sight most likely.

It'll be superconducting tomorrow if it's really superconducting today.

Is that necessarily true?

I'm 200% not a physicist, but it is possible that during transit, minor bumps / temperature changes / ionizing radiation / oscillating E-M fields could screw up the material in a way that matters?

I meant in the abstract sense. They seem to be able to make the stuff with albeit with a very poor yield.

This was my thinking as well.

Not necessarily true. Complex compounds can be susceptible to oxidisation and generally decay and degrade over time.

Apparently, they've offered samples to "serious experimental groups".

"Condensed Matter Theory Center (a Twitter account affiliated with University of Maryland) says they will send samples." - sanxiyn 2 days ago https://twitter.com/condensed_the/status/1684960318718406656

That would mean it's insanely difficult to reproduce.

Not necessarily. Just that the paper is rough and problems in synthesis aren’t well documented or explored.

Devil's advocate: If the existing material and the process to make it can't be replicated, who really cares? Well, aside from the people who might deserve a Nobel. The rest of the world doesn't because we can't all share it like some kind of magical medallion.

I'm on the "Probably a nothingburger" side of things but just getting confirmation that it is possible and some understanding of what the process involved is is a massive jump for science.

If it's actually superconducting we've got a wide variety of ways to inspect what LK99 actually is that will shed a whole lot of light on how to create more of it, or more of a similar superconductor. It'll be one of the most important scientific achievements in our lifetimes regardless of whether or not it can be replicated with the process in the paper.