> Hmm, talcum is hydrated magnesium silicate. It will likely not lose the water http://www.reade.com/Products/Minerals-and-Ores/Talc-Powder-(3MgO*4SiO2*H2O).html Oxide not silicate, obviously ... P. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist