In this invisible world, tiny particles of gold melt at temperatures several hundred degrees lower than a large nugget, and copper, which is normally a goodconductor of electricity, can become resistant in thin layers in the presence of a magnetic field.
Don Melrose, also at Sydney, points out that the gas in the middle of the galaxy might already be so strongly ionised, and thus such a good electrical conductor, that current would leak away rather than build up into a concentration like the Snake.