Ceramics and Quantum Levitation
About this video
A super cool levitator.
At room temperature the ceramic known as Yttrium barium copper oxide has no interaction with magnets, nor does it conduct electricity. However if cooled below -196 degrees Celsius something rather different begins to happen. It becomes a superconductor.
You can learn more about materials with Mark Miodownik in his Christmas Lecture series here. You can also see another great quantum levitation demo here.