Description: Gypsum is a naturally occurring rock which, when ground to a powder and heated, loses most of its moisture. When mixed with water it forms a paste or 'slurry' which sets solid. This simple discovery has made gypsum one of the most useful and versatile building materials and forms the basis of a huge industry producing a wide range of building and medical products. In the Midlands there is a wide belt of gypsum stretching from Uttoxeter to Newark, which has been mined since Roman times.