Deep inside University College London is a collection of some of the worlds most curious substances- from solid sky to magnetic fluids.

The red substance is hydrophobic sand which repels water.

The grey ball is a sphere of silicon nitride which is the hardest man made substance in existence, it can only be scratched by a diamond.

The blue stuff is called aerogel and it was developed by Nasa to catch stardust. It is blue for the same reason that the sky is blue, the light is scattered as it passes through it (Rayleigh scattering). It is now used commercially for its amazing thermal insulation properties.

The white disc is a Bioglass Scaffold which is a human bone regenerator. It is impregnated with stem cells and protein and inserted into the human body where bone gradually forms in its place.

The beige square is Aluminium Nitride which has high performance heat conductive properties. If you hold it in your hand, it will conduct your body heat so efficiently that it can cut through ice as if it were butter.

The last shot is magnetic fluid.  Suspended in an oily fluid are Nanoparticles of iron which react on contact with a magnetic field to form this spiky pattern.  It is used in hydraulic suspension systems and also in computer hard drives, forming a seal around the rotating shaft.