What is Ferrofluid? In short, it is a liquid that responds to magnets and magnetic fields. Ferrofluid is an extremely fine powder, coated with a soap-like material called a surfactant, and suspended in a mineral oil liquid base. It looks like magnetic ink. The resulting magnetic suspension is called a ferrofluid. When no magnetic field is present, ferrofluid behaves and flows like a normal liquid. However, when a magnet or magnetic field is introduced, the ferrofluid is attracted to the field. The ferrofluid aligning itself to the magnetic fields creates fun and interesting shapes and lines, letting you see what a magnetic field looks like. It is called a ferrofluid display. You can even make a ferrofluid clock ...tic toc! <br><br>Please take care when handling ferrofluid. Besides being fun to play with, it also is capable of staining everything it comes into contact with. Please make sure to take care when using it. Note: Some pictures are an example of what can be created with ferrofluid.