The homogeneity of a bulk YBa2Cu3Oxsample prepared by standard methods has been determined. Measurements of the conductivity,Tc(by induction), and xhyphen;ray analysis showed no deviation from bulk material previously characterized as lsquo;lsquo;homogeneousrsquo;rsquo; in the literature; the sample was shown to be inhomogeneous by the eddy current method. We use the samplersquo;s response to multifrequency eddy current probing as a measure of homogeneity. This response is calculated from measurements of the complex impedance of a coil, which contains the sample, as a function of frequency. The homogeneity of the sample after being quenched in air from three successively higher temperatures (650, 700, 800thinsp;deg;C) has also been determined. A rough conductivity profile in one dimension is obtained for all four sample conditions.
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