Salt Peter toby jug finished in a full colorway, designed by Colin Rawson and produced by Hornsea Pottery of Hornsea, England, between 1950 and 1952. Standing up against his brick kiln, Salt Peter is a hardworking potter in the Hornsea region. His left arm forms the handle of the jug. Saltpeter is a common chemical, used for many products and science projects. Saltpeter is the natural mineral source of the chemical potassium nitrate. In pottery, saltpeter is used as a flux, which helps to lower the melting point of the clay and glaze mixture, making it easier to work with. It is also used as a colorant in some glazes.