Barium Carbonate

Barium carbonate is typically used at 0.3–1.0% by weight of the dry ceramic body mix, depending on the sulphate content of the raw materials. A higher sulphate burden from raw clay or feldspar requires a proportionally higher barium carbonate dosage to ensure complete neutralisation.

In ceramic glazes, BaO (formed from barium carbonate during firing) acts as a high-temperature flux that improves glaze melt fluidity, reduces surface tension, promotes glaze smoothness, and contributes to mechanical strength and chemical durability of the fired glaze.

Barium carbonate in its raw powder form requires proper handling precautions as it is toxic if ingested. However, after firing, barium is incorporated into the insoluble glass phase of the ceramic body or glaze and does not present a leaching hazard in the fired product.

Yes, barium carbonate is used in tableware glazes as a flux contributing to gloss, smoothness, and chemical durability. However, its leachability in the raw fired glaze must be assessed and controlled in compliance with food-safe ceramic regulations.

Yes. Barium carbonate decomposes at approximately 1000°C, releasing BaO and CO₂. The BaO then reacts with the glass phase, contributing to densification and vitrification. The CO₂ release must be accounted for in the firing schedule to avoid body bloating or pin holes.