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Ceramic with high electrical conductivity.
Alumina 99 9 100 has exceptionally low dielectric loss.
Most of these conductors are advanced ceramics modern materials whose properties are modified through precise control over their fabrication from powders into products.
Most ceramics resist the flow of electric current and for this reason ceramic materials such as porcelain have traditionally been made into electric insulators.
Some ceramics however are excellent conductors of electricity.
Despite of very low electrical conductivity of most of the ceramic materials there are ceramics possessing superconductivity properties near to zero electric resistivity.
Most high tc ceramics are layered structures with two dimensional copper oxygen sheets along which superconduction takes place.
Aluminas aluminum oxide al 2 o 3 are a commonly used technical ceramic with a range of high performance properties including excellent dielectric behavior.