Ceramics are amongst the most electrically insulating materials known. However, discoveries in the late 20th century have also shown some ceramics to be the most electrically conducting.
The discovery of high temperature (above the temperature of liquid nitrogen) ceramic superconductors has changed superconductivity from an interesting curiosity to a useable technology, with particular applications in the medical field as a superconducting magnet in MRI scanners. Superconductors are also used in NMR and mass spectrometers and in particle accelerators such as the large Hadron Collider.
Typical materials include YBCO (a mixture of the oxides of yttrium, barium and copper) and BiSSCO (a mixture of the oxides of bismuth, strontium and copper).