Masonry oven these primitive-looking ovens were still being produced in Barnstaple potteries as late as 1890". A cloche or cooking bell is like an upside-down, fired ceramic bowl with a handle on top. It is heated in the fire along with a flat rock or open spot on the hearth. The prepared dough is placed on the hot rock or hearth floor, and then covered with the cloche, and perhaps hot coals or ashes for additional heat. The method goes back to ancient Egypt and Greece, and was probably the first form of masonry oven. It is possible to get some of
Compaction of ceramic powders depending on whether the starting materials involve a gas, a liquid or a solid. Examples of methods involving gases are: chemical vapour deposition, directed metal oxidation and reaction bonding, whereas examples of methods involving liquids are: sol-gel process and polymer pyrolysis. Methods involving solids, and especially powder methods, dominate ceramic forming and are extensively used in the industry. The practical realization of ceramic products by powder methods requires the following steps: ceramic powder production, powder treatment, handling and processing, cold forming, sintering and evaluation of the performance of the final product. Since this process permits an efficient production of parts