text: A material demonstrating this phenomenon appears to decrease in weight in a Gouy balance.
full_question: A material demonstrating this phenomenon appears to decrease in weight in a Gouy balance. Anelectron in 2D orbit around a nucleus demonstrates this phenomenon due to Larmor precession, with a magnitude proportional to the radius squared over six times the mass. This phenomenon explains the strong downfield shift of aromatic compounds' ring currents in proton NMR. A normal conductor cooled into superconducting state displays the (*) perfect form of this phenomenon, with a susceptibility of negative one. This phenomenon occurs if all electrons in a material are paired. This behavior could be used to accomplish levitation because it causes materials to repel all B fields. For 10 points, name this type of magnetism contrasted with paramagnetism and ferromagnetism.
first_sentence: A material demonstrating this phenomenon appears to decrease in weight in a Gouy balance.
raw_answer: diamagnetism