At 12:32 PM 3/21/00 +0200, you wrote: >Sorry for this off topic question but i need to find values >for SiO2 permitivity and electrical conductivity; can you >help me ? Try contacting COORS Ceramics in Golden Colorado. They manufacture the stuff for lab use--as in O2 sensors, retorts, whatever. Same company as Coors, the beer. Kelly William K. Borsum, P.E. -- OEM Dataloggers and Instrumentation Systems & San Diego, California, USA