Barium copper-silicate doesn't just have archaeologists and chemists intrigued. At normal temperatures, it's an insulator and is nonmagnetic. Along with its many fine properties - prettiness, historical importance, a hint of aristocratic style — barium copper-silicat has many electrons, some of which spin up and some of which are spin down.
Something unusual happens as the temperature drops and as a magnetic field is applied, although the temperature has to drop pretty far, going down to between one and three degrees Kelvin, and the magnetic field has to be about 800,000 times the strength of Earth's magnetic field. The results are worth it — the electrons seem to merge, taking on one spin, and acting as one electron.
That sounds like an ordinary superconductor, you say. Then you're as foolish as a Phoenician in sub-par purple! Han purple still has a trick up its sleeve. Drop the temperature some more and something happens to the magnetic wave traveling through the substance. At higher temperatures, it propagates like a regular wave, traveling in three dimensions. Get under one degree Kelvin, and it no longer has a vertical component. It propagates in two dimensions only.
