After a few intense weeks of speculation and drama, more and more labs have been able to recreate LK-99, also known as modified lead-apatite. The material was touted as the first-ever room-temperature ambient pressure superconductor, a claim that was met with healthy skepticism and excitement. After all, extraordinary claims require extraordinary evidence.
Arstechnica has a great writeup here. Seems like the process is just so variable that recreating the exact substance will be very difficult, even if the original sample is confirmed - akin to Flash’s speed force experiment, or Steve Roger’s super serum.