Masonry oven India, tandoors are traditional clay ovens, although these days modern electrically fired tandoors are available. The open-topped tandoor is a transitional design between the earth oven and the Roman-plan masonry oven. In the precolumbian Americas, similar ovens were often made of clay or adobe and are now referred to by the Spanish term "horno" (meaning "oven"). Horns are also traditional in the American Southwest. The traditional direct-fired masonry design is often called a "Roman" or "black" oven and dates in Western culture to at least the Roman Republic. It is known as a black oven because the fire generates soot
St Austell Clay Pits has designated a large area of active and disused mine workings in the St Austell area as an Important Plant Area, with the same name as the SSSI. This area includes all the SSSI sites, as well as many others. It is thought that the protected areas will act as a source for colonisation for the western rustwort to other locations in the surrounding china clay area. St Austell Clay Pits St Austell Clay Pits, (Cornwall, England, UK,) are a group of locations within active china clay quarries that form a single Site of Special Scientific Interest (SSSI) and Special