The name of “Feldspar” refers to group of Aluminum Silicate of potassium, sodium and calcium. The chief use of Feldspar is in the Ceramic and Glass Industries. Smaller quantities are used in the manufacturing of Tiles, Whiteware, and Sanitaryware. Other uses of Feldspar include Catalysts, Acid resistant and Decorative Stone as a flux or binding agent in certain scanning Soaps and artificial teeth.
|Silica||SiO2||68% (+/- 1%)||70% (+/- 2%)|
|Alumina||Al2O3||18% (+/- 0.5%)||18% (+/- 2%)|
|Sodium Oxide||Na2O||10.00% (+/- 1%)||8% (+/- 1%)|
|Pottasium Oxide||K2O||0.5% (+/- 0.5%)||4% (+/- 1%)|
|Calcium Oxide||CaO||Nil||0.25% (+/- 0.05%)|
|Magnesium Oxide||MgO||Nil||0.25% (+/- 0.05%)|
|Ferric Oxide||Fe2O3||0.06% (+/- 0.05%)||0.1%|
|Loss on Ignition||LOI||0.1%||0.2%|
In ceramic bodies, the main vitrifying (fluxing) agent is feldspar. The majority of whiteware bodies contain good proportions of feldspar. It acts as a flux. In the ceramic industry, the flux is defined as that portion of the body which develops glass phase. This is provided mostly by feldspar. The amount of flux in a ceramic body should be only in such a proportion as to develop the desired amount of vitrification. If an excess of flux is added, the fired body becomes very glassy and consequently, brittle.
The glass and ceramic industries are the major consumers of feldspar and account for 95% of the total consumption.
Feldspar is generally used in making the body composition of several types of porcelain, china, and earthenware and also in the preparation of glazes and enamel. It is also used as an important ingredient in the glass sand batch. Used as a bonding agent in the manufacture of bonded abrasives like wheels and discs of garnet, corundum, emery, etc.