Used in the production of ceramic glazes and glass to improve hardness and durability. Commonly employed in the manufacture of ferrites for electronic components. Acts as a flux in tile and sanitaryware production, lowering melting temperatures. Utilized in rat poisons and pesticides due to its toxicity to rodents. Applied in the steel industry to remove sulfur impurities. Also found in some types of welding rods to stabilize the arc and improve weld quality.