Fumed silica (also known as pyrogenic silica and silicon dioxide) is one of the lightest substances known. Fumed silicas are very light and fluffy and have bulk densities of 3 lbs/cu ft (38 kg/cu m). Silicon metal and alloys are produced in electric furnaces. The raw materials include quartz, coal, and wood chips. The smoke that results from furnace operation is collected and sold as fumed silica. Depending on the processing, fumed silica may be used as a hydrophilic or a hydroponic.
From sidewalks and foundations to paint cans, printed pages and pet litter boxes, fumed silica’s application as a universal thickening agent means it can be found in widely dissimilar places. Slightly abrasive and light-defusing, fumed silica is used in personal care products such as toothpaste and cosmetics.