Definition:
Barium carbonate (noun) is used in pottery as a secondary flux, especially when a satin matte or matte glaze is desired.
Barium carbonate (BaCO3) is lighter than barium oxide (BaO) in weight and does not settle in the liquid glaze batch as fast. It is often used, therefore, to introduce barium into the glaze. In nature, barium carbonate occurs as the mineral, witherite but both barium carbonate and barium oxide are more frequently commercially created from other minerals for use in glazes.
Barium is poisonous. Handle raw forms of barium with care. Barium frits are safer than barium carbonate, and barium carbonate is safer than barium oxide. Do not use barium in dinnerware.
Examples: The chemical bonds of barium carbonate require a reduction atmosphere as well as heat to break them.
Barium carbonate (noun) is used in pottery as a secondary flux, especially when a satin matte or matte glaze is desired.
Barium carbonate (BaCO3) is lighter than barium oxide (BaO) in weight and does not settle in the liquid glaze batch as fast. It is often used, therefore, to introduce barium into the glaze. In nature, barium carbonate occurs as the mineral, witherite but both barium carbonate and barium oxide are more frequently commercially created from other minerals for use in glazes.
Barium is poisonous. Handle raw forms of barium with care. Barium frits are safer than barium carbonate, and barium carbonate is safer than barium oxide. Do not use barium in dinnerware.
Examples: The chemical bonds of barium carbonate require a reduction atmosphere as well as heat to break them.
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