The shapes you see in these image are about the size of a thumbnail. They are created by mixing ferrofluid with watercolour and putting it into a magnetic field. Ferrofluid is a magnetic solution with a viscosity similar to motor oil. When put under a magnetic field, the iron particles in the solution start to rearrange, forming the black channels and separating the watercolours from the ferrofluid. The result is these peculiar looking structures.