In the past, magnets were nothing to fear. The small ceramic type long used on refrig erators were barely strong enough to hold up a piece of paper. The same size magnet today can kill you. . Every electron in a material has a spin that creates a tiny magnetic field around it. Normally these electrons spin in random directions, canceling each other out, but in permanent magnets, some of the electrons are locked into alignment, producing an overall magnetic field. The stronger this lock-in, the stronger the magnet. Powerful neodymium-iron-boron magnets are used in everything from jewelry to motors. With the development of new alloys and processing methods, they are getting stronger and stronger, to the point that even very small ones can be dangerous. If you swallowed two separately and they were to find each other, they could puncture your intestinal walls and cause a fatal infection.
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