Lambourne round dish

Bone china

Bone china is a kind of porcelain body initially used in Great Britain in which calcined ox bone, bone ash, is an important ingredient. It is distinguish by high whiteness, strength and translucency. lambourne round dish may be an example of this process.

The first use of bone ash in ceramics is attributed to Thomas Frye in seventeen-forty-eight in which he used it to develop a type of soft-paste porcelain. In As the eighteenth century drew to a close, Josiah Spode undertook further developments, and duly popularised it, by mixing it with china clay, kaolin and China stone to compete against the imported Oriental porcelain.

The original basic recipe of six parts bone ash, three and a half parts china clay, and four parts china stone remains the standard English body.

Bone china production ordinarily makes use of a two stage firing process where the initial "biscuit" is fired without a glaze at 1280°C (2336°F) giving a semiopaque product and then it is glaze, or glost, fired at a lower temperature under 1080°C (1976°F). lambourne round dish is probably made using this process.

Soft-paste porcelain

Soft-paste porcelain is a kind of porcelain and consequently a ceramic product.

Its history dates from the initial trials by European potters to imitate Chinese porcelain by using combinations of china clay and frit or ground-up glass; soapstone and lime were known to have also been employed in some formulations. As these early compounds were prone to high pyroplastic collapse, or slumping in the oven at raised temperature, it was uneconomical to produce them. Concoctions were later developed based on quartz, kaolin, nepheline syenite, feldspars and other feldspathic rocks. These were technically superior and continue in production to this day.

Hard-paste porcelain

Hard-paste porcelain is a hard, dense ceramic that was originally produced from a mixture of the feldspathic rock petuntse and kaolin fired at very high temperature. It was first manufactured in China in about the ninth century.

The secret of its manufacture was unknown in Europe until the early 1700s, when Böttger of Meissen, Germany found the formula. Regardless of attempts to keep it secret, the procedure spread to other German ceramic factories and finally became widely known throughout Europe.

Hard-paste porcelain is fired at a range of temperatures to make a multitude of unique end results. Depending on the firing approach, hard-paste porcelain can be made to resemble stoneware or earthenware. Mainly however, it is not necessary to use hard-paste porcelain for these lower temperature ceramics. Hard-paste porcelain can be utilized to manufacture porcelain bisque, a hard crystalline material fired at extremely high temperatures in a pressure controlled environment. This technique gives birth to a translucid bright white ceramic. Unlike other bisque ceramics, porcelain bisque is almost impermeable by water, making it unnecessary to glaze the body before painting. Manufacturers such as Hummel, Precious Moments and Lladro make use of hard-paste porcelain exactly for this reason, this could include lambourne round dish.