A 92.5 K REBa2Cu3O7-delta superconductor starting from natural mixture of rare earth elements

The processing and characterization of a REBa2Cu3O7-delta, sample supercond uctor is described, where RE corresponds to a natural mixture of rare earth elements extracted from xenotime mineral. This mixture contains no Pr and, contrary to previous studies, can substitute the yttrium atom in YBa2Cu3O7 -delta, (YBCO) without deleterious effects in structural and superconductin g properties, as measured by X-ray diffraction, resistivity and magnetoresi stivity. Our sample presented T-c = 92.5 K and average lattice parameters a = 3.821 Angstrom, b = 3.896 Angstrom and c = 11.686 Angstrom, which are ve ry similar to YBCO properties. Considering that the process of separation o f Y (and other pure rare earth elements) from any natural mixture involves high costs, our system represents a practical alternative to YBCO compound.