Recently[1], there was an exciting claim that a new type of material could conduct electricity perfectly at room temperature (this is what is meant by "superconductivity")[4]. This material was a version of lead-apatite [2], a type of mineral, that was altered with certain additions and made by combining two other materials, lanarkite and copper phosphide.
The researchers writing this report wanted to check if this claim was true. So, they made the same types of materials (lanarkite, copper phosphide, and the altered lead-apatite) and tested how they conducted electricity and reacted to magnets.
What they found was that lanarkite (Pb2SO5) didn't conduct electricity well at all, and copper phosphide Cu3P) conducted electricity similar to a semiconductor [3]. The altered lead-apatite, which was supposed to be the superconductor, behaved more like a semiconductor (a type of material that can sometimes conduct electricity, depending on conditions).
Also, a key property of superconductors is that they repel magnets. But when the researchers put a magnet near their lead-apatite, there was no repulsion.
Because of these tests, they're suggesting that the original claim about this room-temperature superconductor should be re-examined more carefully. It doesn't seem to behave like a superconductor in their tests.
[1] https://news.ycombinator.com/item?id=36864624
[2] https://en.wikipedia.org/wiki/Apatite