Feldspar & pegmatites for ceramics
Higher fusibility and strength in ceramics
Feldspar and pegmatite can be used as the main vitrifying or fluxing agents in ceramic bodies. As feldspar melts gradually over a range of temperatures, it greatly facilitates the melting of quartz and clays and, thanks to an appropriate mixing, it allows modulations of the melting stage.
In tiles and large surfaces, feldspar is a major ingredient of the body. Our RF4 feldspar solution has unique properties which are highly valued by our customers: it limits shrinkage during firing, allowing our customers to consume less raw materials and it contributes to a better balance of the fluxing oxides, which allows to lower the firing temperature or shorten the firing cycle, resulting in energy and CO2 savings. In addition, it enhances the mechanical strength of the tiles and improves the body whiteness.
In tableware, feldspar gives a good fusibility for a product without defects and it strengthens and ensures the durability of fired bodies.
Pegmatites are rocks composed of several minerals, usual feldspar with potassium, quartz and kaolin. This gives them a natural fluxing capability and, thanks to their low level of colored oxides, they are especially suitable for white tableware.
In sanitaryware, the use of feldspar enables vitrification thus making the fired piece non porous. Relative alkali content (sodium to potassium ratio) enables to control the aggressiveness of vitrification and influences final porosity and fired deformation.
Feldspar is also used as a source of alumina and alkalis in glazes.
Our feldspars and pegmatites are characterized by their high potassium content and low iron and titanium content – ideal for whiteness and translucency in tableware and sanitaryware.
We produce feldspar using a strictly controlled production process, tailored to the technical requirements of tableware manufacturers. We can also help you to ensure that the proportions of feldspar in your body recipe are exactly right to avoid over-vitrification during firing.
We mine and process feldspar at our operations in France, Turkey, Thailand and India, and we also have pegmatite production facilities in Germany.
- Enables to lower the firing temperature or shorten the firing cycle, resulting in energy and CO2 savings thanks to a better balance of the fluxing oxides
- Allows consuming less raw materials by limiting shrinkage during firing
- Enhances the mechanical strength of the tile
- Improves the body whiteness
Imerys feldspar main products
Our RF4 feldspar solution has unique properties that are valued for the production of tiles, and especially for large slabs:
- Limits shrinkage during firing, allowing our customers to consume less raw materials;
- Contributes to a better balance of the fluxing oxides, which allows to lower the firing temperature or shorten the firing cycle, resulting in energy and CO2 savings;
- Enhances the mechanical strength of the tile;
- Improves body whiteness.
Minspar 200 is a flotation grade mixed feldspar used in glazed and clay bodies.
- is a high quality mixed feldspar milled to 170 mesh specifications which provides a slightly coarser option to maximize cast rate.
- is a high quality sodium/ potassium/ calcium aluminum silicate ground to 170 mesh for ceramic applications, offering a low iron oxide and high alkali oxide content per unit of alumina.
Minspar 250 is a high quality sodium/potassium/calcium aluminum silicate offering low iron oxide and high alkali oxide per unit of alumina making it ideal for use in a wide variety of ceramic applications.