Patent ID: 7709418

Claim:
A composition of matter comprising a Y—Ba—Cu—O complex of nominal formula: (Y 1−x Ba x ) a Cu b O y , wherein “x” is about 0.01 to 0.5, “a” is about 1 to 2, “b” is 1, and “y” is about 2 to about 4, containing a superconductive crystalline phase consisting essentially of Y, Ba, Cu and O which has zero electrical resistance at 77° K or above, said superconductive crystalline phase having a crystal structure uncharacteristic of that of a K 2 NiF 4 crystal structure, and said superconductive crystalline phase being present in said composition of matter in a quantity sufficient to provide the composition with a diamagnetic signal at 4.2° K corresponding to at least 24% of the superconducting signal of a lead sample with similar dimensions.