Magnesium carbonate, an important resource for the ceramics industry
Magnesium carbonate has only recently started to be used in the ceramics industry. In fact, magnesium carbonate is used in only some specific situations: either as a matting agent for “Sassuolo white” glazes, to obtain a velvet, dulled surface, or a fluxing agent for shimmed screen-prints, or as flux for mixtures, or in ceramic roller engobes.
Added in very low percentages - about 5% - to glossy glazes, it has a dulling velvet effect to increase the richness of the glaze and to make it light and pleasing to touch. For this use, it is very important to ensure the correct dosage, but above all to use pure magnesium carbonate, free of dolomite and with very little free quartz to reduce the surface tapping as much as possible.
As a flux for mixtures, magnesium carbonate is very strong so in comparison to talc it needs to be added in smaller percentages, but above alol, as in the case of glazes, it must be free of all other components. Our magnesium carbonate comes from West Park mining quarries in Turkey, and is particularly pure and thus very much suited to this kind of use.
As a parting agent in roller engobes, magnesium carbonate – improperly referred to as “magnesite” – is in some cases used together with kaolin and alumina. A mixture of high percentage magnesite adn 10% kaolin makes a good eutectic, too keep the tiles from stiking to the rollers during firing.
As mentioned before, we follow this product straight from the quarry, wich is located in the centre of Anatolian Turkey. The West Park mining quarries have an excellent production level, in terms of both quality and quantity.
The product is checked by expert geologist on a daily basis and granulated to approximately 1 mm.
This allows for a uniform quality, but above all to avoid powder, wich could cause injury when opening the sacks. This material can be supplied directly in big bags, or in 25 Kg sacks for easy engobe preparation.