Density

ZIRCONIA	HIGH LOW	6	Toughness Mechanical Strength High Heat Resistance Corrosion Resistance
ALUMINA		3.8	General use Wear resistance Electrical insulator Dielectric strength Low dielectric loss
ALUMINIUM NITRIDE		3.2	Thermally stable Electrical resistivity
SILICON NITRIDE		3.2	High toughness Thermal shock resistant Tight tolerances
SLIICON CARBIDE		3.2	Hardness Mechanical strength Variable electrical resistivity Distinct properties that can be tailored
STEATITE		2.8	Good dielectric strength Low dielectric loss
CORDIERITE		1.8	Good thermal expansion Excellent thermal shock resistance