A method of fabricating bulk superconducting material such as RBa2Cu3O7- delta where R is La or Y comprising depositing a thin epitaxially oriented film of Nd or Sm (123) on an oxide substrate. The powder oxides of RBa2Cu3O7- delta or oxides and/or carbonates of R and Ba and Cu present in mole ratios to form RBa2Cu3O7- delta , where R is Y or La are heated, in physical contact with the thin film of Nd or Sm (123) on the oxide substrate to a temperature sufficient to form a liquid phase in the oxide or carbonate mixture while maintaining the thin film solid to grow a large single domain 123 superconducting material. Then the material is cooled. The thin film is between 200 ANGSTROM and 2000 ANGSTROM . A construction prepared by the method is also disclosed.