He takes a petri dish of ice in the process of freezing and sandwiches it between two polarising filters. As white light passes through the first filter it polarises, causing the rays to vibrate in the same plane.
Ice crystals split light into two rays which travel at different velocities through the ice in a phenomenon known as birefringence. When the rays are recombined at the second polarising filter there is a phase difference causing the interference needed to create these colours.
The colours are determined by the thickness and lattice structure of the ice. Varying the thickness will produce a variety of patterns.
Although water ice can be found throughout the solar system, the lattice structures vary due to the differing temperatures and pressures of their formation.
Only the ice found on Earth has the correct structure to produce a frizion.
See here for more of Wasilewski's images.