The invention provides a superconductor comprising particles made of a
superconductive material, and a conductive material. The conductive
material is selected to be driven to a superconductive state when in
proximity to the superconductive material, and preferably at least
includes bismuth. An unbroken length of the conductive material is
located sufficiently close to a plurality of the particles to be driven
to a superconductive state by the superconductive material.