Novel materials derived from minerals at high P-T

We have constructed and operated versatile miniature pressure cells designe d for the in situ characterization of materials under combined high pressur e-temperature (P-T) conditions. This provides an opportunity conveniently t o perform laboratory experiments to synthesize and characterize novel mater ials that may be stable only under high P-T conditions. The synthesis proce ss may then be scaled up to an industrial level provided that such phase st abilization occurs under modest P-T conditions. The pressure anvils consist of cubic-zirconia, sapphire or diamond to obtain maximum pressures of 10-3 0 GPa. I cite selected examples of materials and minerals that have been in vestigated in our laboratory, where the properties of the crystalline high- pressure phase are radically different from those at ambient pressure, for example, cubanite (CuFe2S3) and troilite (FeS). I discuss the possibility o f pressure-induced amorphization and emphasize the occurrence of this pheno menon in mineral-related materials.