Diatoms are tiny phytoplankton that have cell walls made of silica. They are well-known for having a huge diversity of shapes and patterns - in fact, there are over 100,000 species, so many look vastly different from each other. They are not limited to the oceans - they also live in freshwater, damp surfaces, and in soil. It turns out that in the Victorian era, scientists that looked at diatoms under microscopes liked to arrange them in different interesting patterns, which became an art form known as diatom arrangement. The only person still known to practice this professionally (and make money from it) is a biologist from the UK named Klaus Kemp. He had to learn how to create the arrangements from scratch because Victorian diatomists had not recorded their techniques. Matthew Kilip created a short documentary on how Kemp creates these intricate and beautiful arrangements.