"Accomplished by a team at the Huazhong University of Science and Technology and posted 30 minutes ago.
Why this is evidence:
The LK-99 flake slightly levitates for both orientations of the magnetic field, meaning it is not simply a magnetized piece of iron or similar 'magnetic material'. A simple magnetic flake would be attracted to one polarity of the strong magnet, and repelled by the other. A diamagnet would be repelled under either orientation, since it resists and expels all fields regardless of the polarity.
Caveats
There is no way to verify the orientation of the strong magnet in this video, also, there are yet to be published experimental measured values of this sample. Diamagnetism is a property of superconductors but without measured and verified data, this is just suggestive of a result.
Take-away
If this synthesis was indeed successful, then this material is easy enough to be made by labs other than the original research team. I would watch carefully for results out of Argonne National Lab, who are reported to be working on their own synthesis of a sample.
This overall corroborates two independent simulation studies that investigated the original Korean authors claim about material and crystal structure, and both studies supported the claims.
Lawrence Berkeley National Lab: https://arxiv.org/pdf/2307.16892.pdf
Shenyang National Lab: https://arxiv.org/pdf/2307.16040.pdf "
Still don't know what a LK-99 is.
It's an alleged superconducting material that will work at room temperature.
Room temperature and pressure. The two are intrinsically linked.
That really depends. Offices are usually low temperature and very high pressure environments.
Ah, that one.