These fun little wonders of physics are an addictive novelty. Toss them up near each other, when they contact each other they vibrate rapidly, and make a unique singing chirp. These singing magnets are fascinating visually. Watch their polished hematite surfaces glimmer and vibrate. The magnetic hematite singing marbles make a great desk toy because you can make strong magnetic chains.
Warning: small magnets can be very dangerous to young children if they eat them.