Pottery examples

True and colloidal Pumpable suspen- Examples filter- 100 mesh or less. Larger than 100 Examples pottery. Examples paper. Examples veneer. 

Absorption - Processes water can be removed from a material by the capillary action of porous bodies. An example is the cream of clay and water used for casting pottery, which is deprived of the greater part of its water by placing it in molds of plaster of Paris. The capillary character of this mold withdraws the water from the liquid clay mixture and deposits upon itself a layer of solid clay, the thickness of which is controlled by the time of standing. Certain types of candies, such as gumdrops, are dried mainly by contact with the starch molds in which they are cast. The drying effect of sponges, towels and materials of this kind is due to this same action. 

Dusts and fumes have been a part of industrial life for many years and the hazards associated with them are well known. The diseases and respiratory disorders found in foundries, potteries and cotton works are examples that are familiar to many. These need not occur with a better understanding of control measures and more efficient equipment. 

For most people, the word "ceramics" conjures up the notion of things like china, pottery, tiles, and bricks. Advanced ceramics differ from these conventional ceramics by their composition, processing, and microstmcture. For example ... 

Product applications include the aerospace, automotive, chemical and petroleum industries eincient examples include pottery and glass vessels as well as Egyptian mummies. 

The Components of Materials. The composition of most materials -whether of natural origin, such as minerals, rocks, wood, and skin, or made by humans, as for example, pottery, glass and alloys - includes several kinds of components major, minor, and trace elements (see Textbox 8). 

Primary clay, for example kaolin, is colorless, and when such clay is heated to a high temperature it produces white ceramic materials. Most pottery, however, is colored its color is due to the fact that most of it was, and still is, made not from primary but from secondary clay. Secondary clay contains minerals other than clay, and colored metal ions in them endow the pottery with their color. Iron ions (in iron oxides), for example, tend to make pottery yellow, brown, or red, and manganese ions (in pyrolusite, a mineral composed of manganese oxide) make it either dark or black. 

The simplest and coarsest type of pottery is a lightweight, very porous, and typically red-colored terracotta that is fired at temperatures below 850°C. Much of ancient pottery, for example, is of the terracotta type. Excavations in the Near East have revealed that primitive terracotta vessels were being made there more than 8000 years ago characteristic types of terracotta were developed in China by about 5000 b.c. 

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