Ceramic stoneware usually burned on average at 4- cone cone 11 (1186 0 C-1315 ° C), so it has a temperature of ripeness between Earthenware and porcelain. Stoneware clay bodies are known as good because of its strength, has natural colors, is harsh and somewhat crystaled. As well as porcelain, stoneware when burned at a temperature where the clay becomes mengkaca then the result will be watertight, but generally not too mengkaca stoneware.
Cook stoneware glaze and body at the same temperature so that it will form a glaze perfect accuracy. The types of stoneware that developed in Europe in 1600 and 1700 using the oxides of cobalt and manganese to make stoneware black, agateware (also called marbleware or variegatedware) is an imitation agatestone and produced with a combination of dyes clays that differ in a single body ,
Stoneware in the past typically generated and natural clay containing feldspar and silica is burned so that it becomes solid and porous. As well as the natural clay fireclay, clay pipes for water, and clay to make bricks can be used directly without the addition of other materials and can be used for the establishment by hand or lap. Most clay is prepared for commercial purposes are usually made of some sort sepertifeldspar clay, kaolin, quartz, fireclay, and ballclay made in a particular formula.
Fuel stoneware colors including gray, beige, brown, dark brown, and orange. Stoneware clay usually contains elemental iron (Fe), titanium (Ti), zinc (Zn) .It is this one that distinguishes between porcelain stoneware to porcelain because it does not contain iron element thus providing characteristic white porcelain. The natural iron content in the soil such as iron, ilminite, or manganese will change the surface glaze that when burned produces brownish iron spotspot effect.
47. Picture stoneware clay products are ready to burn
Excess weight clay stoneware is:
1) plasticity is good, so it can be used with a variety of engineering.
2) Strong but not menggelas.
3) Depreciation low.
4) Has the natural color of the soil.
5) It has spots of iron.
6) Having the nature of the prevention of bloating (inflate).
7) Solid and watertight.
8) Has the nature resistant to temperature shock.
9) Has the nature merges with glaze.
Most of stoneware ceramic body is made of a material or materials selected for specific purposes and objectives, among others:
1) To increase plasticity, can be used ballclay up to 30% or red clay to 20%.
2) To increase the melt is generally used flux nonplastis as much as 5% talc or chalk (whiting) 10%.
3) To increase the hardness can be used kaolin, quartz approximately 15% -20%, sand or grog ideally using the powder / granules of goods biscuit or use powdered refractory bricks.
4) To produce clay color can be added to the red clay, Ocher about 5% -10% or metal oxide 5% -10%
5) To form textures, can use grog, sand, or crushed fireclay (refractory bricks) to as much as 25%.