... . 4.almost insoluble in water, aqueous ammonia Potassium Fluorosilicate1. Uses: Potassium fluorosilicate can be applied in wood preservation, ceramic ... and optical glass. Potassium fluorosilicate can be used for smelting of aluminum and ... in hydrochloric acid. It is decomposed by heat to potassium fluoride(KF) and silicon tetrafluoride(SiF4), and hydrolyzed in ...