Feldspars play an important role as fluxing agents in ceramics and glass applications, and also are used as functional fillers in the paint, plastic, rubber and adhesive industries.
Feldspar is an important ingredient in the manufacture of glass and an important raw material, because it acts as a fluxing agent, reducing the melting temperature of quartz and helping to control the viscosity of glass.The alkali content in feldspar acts as flux, lowering the glass batch melting temperature and thus reducing production costs.
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