Dry strength is the nature of the clay body of ceramic objects that have been dried, it is very important because the nature of ceramic objects to be strong enough to be lifted, refined, and arranged in a furnace. Clay that has a high plasticity will be higher the dry strength.<\/p>\n
Ballclay is a material that has a good dry strength, but when made objects will arise cracked.
\nDry strength is affected: grain fineness plasticity curing time (aging) the amount of water forming mixing with other materials forming techniques<\/p>\n
Color Burn<\/strong> After experiencing the process of burning clay color that sometimes appears different with colors in the raw state, it is influenced by substance \/ material contained therein is chemically bound. Organic impurities would be burned out at the time of the combustion process takes place, while the materials are chemically bonded to cause the clay to color.<\/p>\n Clay color is caused by substances that pollute, gray to black carbon and contain the remains of plants, containing red iron oxide (Fe) but can also be produced by adding dyes such as cobalt (Co), cupper (Cu ), chromium (Cr), iron (Fe), manganese (Mn). In general, the type most widely Earthenware clay containing oxides of iron (Fe). Fuel color (biscuit temperature of 900oC) pure clay Sukabumi, Pacitan, Malang, Bojonegoro, and Singkawang as shown in the figure below.<\/p>\n<\/div>\n
\nClay in the raw state obtained from the place of origin (deposits) have a variety of colors such as beige, tawny, brownish red, gray, and black, the color difference is influenced by the ratio of the levels of ingredients include a mixture of clay or dirt humus (organic ), iron oxide (Fe), etc..<\/p>\n
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