Porcelains bone China

Bone china has a composition similar to that of porcelain, but at least 50 percent of the material is finely powdered bone ash. Like porcelain, bone china is strong and can be formed into dishes with very thin, translucent walls. Stoneware is a dense, hard, gray or tan ceramic that is less expensive than bone china and porcelain, but it is not as strong. As a result, stoneware dishes are usually thicker and heavier than bone china or porcelain dishes. 

First, a solid model of the object has to be made. This would originally have been done in solid clay or with a pre-existing form. Nowadays it would generally be made of plastercine or Acrylic. These models are always oversized as the finished article shrinks both in the mould and in the kiln. Earthenware, bone china and porcelain may shrink by as much as 15 to 20 percent Parian is considerably more prone to shrinkage and may lose as much as 25 per cent. 

Around 1750, porcelain was produced with bone ash in England and given the name bone china ... 

Bone China has a similar recipe to hard-paste porcelain, but with the addition of 50% animal bone ash (calcium phosphate). This formulation improves strength, translucency, and whiteness of the product and was perfected by Josiah Spode at the end of the eighteenth century. It was then known as English China or Spode China. ... 

We stated at the beginning that this chapter is the pottery chapter. We will now summarize areas in which many of the techniques described above have been used, in some cases for milleimia, in pottery then we can do the same for glass. Classical porcelain can be as thin as a sheet of paper (<0.2 mm). Bone china, so called because even today it is made by adding -50% bone ash to a conventional hard-porcelain clay mixture, can be so thin that it is translucent. This ingredient is so critical that the UK imports bone ash from Argentina. 

Industrial applications. Filler for paper and board, coating clays, ceramics, bone china, hard porcelain, fine earthenware, porous wall tiles, electrical porcelain, semivitreous china, glazes, porcelain, enamels, filler for plastics, rubbers and paints, cosmetics, insecticides, dusting and medicine, textiles, and white cement. 

China. BS 5416 specifies this to be pottery with water absorption 0.2% and tranlucency 0.75% (assessed by comparison with standard test pieces) See also bone china. In the USA, however, ASTM-C242 defines the word as any glazed or unglazed vitreous ceramic whiteware used for nontechnical purposes, e.g. dinnerware, sanitary-ware, and art-ware, provided that they are vitreous. The combined nomenclature (q.v.) equates this term with porcelain (q.v.). 

English Pink. See chrome tin pink. English Translucent China. Ceramic tableware, etc., introduced in 1959 by Doulton Fine China Ltd, Burslem, England. In contrast to bone china it is feldspathic, but differs from Continental porcelain in that it is biscuit fired at a higher temperature than the glost fire. English and Turner Factors. See... 

PORCELAIN, SEMI-PORCELAIN, CHINA, BONE CHINA, STONEWARE. 

Ceramics are inorganic solids, usually oxides, which contain ionic and covalent bonds. The material, formed by sintering at high temperatures, ranges from amorphous glass-like material to highly crystalline solids, from insulators to conductors or semiconductors. They include earthenware, which is fired at 1,100-1,300 K and a porosity of about 8% fine china or bone china, fired at 1,400-1,500 K with a porosity of less than 1% stoneware, fired at over 1,500 K with a porosity of about 1% before glazing and porcelain which is fired at over 1,600 K and has a much finer microstructure than either stoneware or bone china. 

Soft-paste porcelains differ from the above porcelains by their greater translucidity and lower sintering temperature. Chinese porcelains and porcelains for dental implants belong to this category. English porcelains, known as bone china, constitute a particular class. 

Figure 4.8. Temperature influence on the shrinkage speed of a hard-paste porcelain, a bone china and a vitreous china...

SLA 93] SLADEK R., Bone china - a high quality soft porcelain as an enrichment of modern table art ,Interceram, vol. 42, p. 100-102,1993. 

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