Metal casting is arguably the earliest and most influential industrial process in history. In the metal casting process, metal shapes are formed by pouring molten metal into a mold cavity, where it is cooled and later extracted from the mold. Metal casting is a modern process with ancient roots. Historically it is used to make complex and/or large parts, which would have been difficult or expensive to manufacture using other manufacturing processes. The term ‘casting’ is also used to describe the part made by the casting process which dates back 6000 years. It facilitates cleanliness and sanitation in building and is a retardant to the spread of fire.Metal casting is defined as the process in which molten metal is poured into a mould that contains a hollow cavity of a desired geometrical shape and allowed to cool down to form a solidified part. However, as a surface material for interior walls and ceilings and to a lesser degree for exterior walls, plaster remains in common use. Plaster as a medium of artistic expression waned by the 19th century, when imitation and mechanical reproduction displaced this creative art. Earlier extant specimens of the plasterers’ skill in England are the pargeted and ornamented fronts of half-timbered houses. The ornamental plaster ceilings of England during the reigns of Henry VIII, Elizabeth I, and James I are still admired. Plaster was frequently used to cover the exteriors of temples, a technique commonly known as stucco, in addition to covering the interiors, in some cases even when the building was made of marble. Greek artisans had achieved high quality earlier than the 5th century bce. Very early in the history of Greek architecture (e.g., at Mycenae), plaster of a fine white lime stucco was used. For their finest work the Egyptians used a plaster made from calcined gypsum that is identical to plaster of paris. The principal tools of the plasterer of that time were in design and purpose like those used today. The pyramids of Egypt contain plasterwork executed at least 4,000 years ago that is still hard and durable. Some of the earliest plastering extant is of a quality comparable to that used in modern times.
More lasting and sightly materials in time replaced mud. Evidence indicates that primitive peoples plastered their reed or sapling shelters with mud, thus developing more durable structures and more effective screens against vermin and inclement weather. Plastering is one of the most ancient building techniques. Plaster, a pasty composition (as of lime or gypsum, water, and sand) that hardens on drying and is used for coating walls, ceilings, and partitions.
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