“…The contactless method developed by us [7,121 is most suitable for determining the volume fraction of the superconducting phase in a sample over a wide frequency range. In fact for YBa,Cu,O, (71 and DyBa,Cu,O, [12] the product of Meissner susceptibility and volume fraction was found to be independent of frequency up to 10 MHz. One special purpose of doing these measurements on the present samples was to find our whether the amount of superconducting grains could be estimated by this method in the sample n = 0.2, where superconductivity could not be detected by dc resistance measurements up to liquid N, temperature.…”