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Feldspar Applications:



More than 70% of the feldspars produced in the EU are used in the ceramic industry, and most of the rest in the glass production.
In the manufacture of ceramics, feldspar is the second most important ingredient after clay, acting functionally as a flux. Indeed, feldspar does not have a strict melting point, but melt gradually over a range of temperatures. This greatly facilitates the melting of quartz and clays and, through appropriate mixing, allows to modulate this important step of ceramic making.



In the glass industry, feldspars are used for their alumina content and their content of alkali. The alkali act as flux ingredients, lowering the batch melting temperature and therefore contributing to the reduction of production costs. Alumina acts as a matrix former, reducing the tendency for glass to devitrify. It also acts as a stabiliser which improves the chemical durability of glass, as well as its physical resistance. The addition of feldspar to glass also improves the workability of the material produced, making it more suitable e.g. for pressing.




Feldspars are also used as fillers and extenders in applications such as paints, plastics and rubber. Beneficial properties of feldspars include good dispersability, chemical inertness, stable pH, high resistance to abrasion, low viscosity at high filler loading, interesting refractive index and resistance to frosting. The products used in such applications are generally fine-milled grades.


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