Fine China Dinnerware designated as "Fine China" usually indicates that feldspar, a glassy and hard crystalline mineral made up mainly of aluminum silicates rather than bone ash has been used as the fluxing (fusing or bonding) agent. Fine china does not have the pure white body seen in bone china - it tends to have a grey-white hue.

Bone China  The ingredients of bone china are china clay, china stone, silica, alumina, alkalies, lime and bone ash. It is fired at high temperatures of 2300 to 2500 degrees Fahrenheit. In the best grades of English bone china 50% or more of the body consists of refined bone ash prepared from specially selected animal bones which are reduced to a fine powder by heat. The bone is mixed with the finest china clays and highest quality Cornish stone. Specially skilled workers are needed in the manufacture of bone china and the best and most highly skilled in the world are found in the pottery district of England

Porcelain Today the term porcelain is used loosely to describe shaped clay fired at extremely high temperatures, much higher than used in conventional china manufacture. When shaped thin enough porcelain is translucent, as is bone china. As a matter of fact, the recipe for both porcelain & bone china are closely aligned. The term "bone china" however, indicates that calcined animal bone ash (usually 25% to 50% of the total mixture) has been added to the basic batter of white clay and pulverized stone.

Semi-Porcelain A harder, more durable form of earthenware. The principle ingredient is china clay or feldspathic clay baked at a high temperature. Often the term semi-porcelain and high-grade earthenware are interchangeable.

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