- Ammonium fluorosilicate (also known as ammonium hexafluorosilicate, ammonium fluosilicate or ammonium silicofluoride) has the formula (NH4)2SiF6.
- It is a toxic chemical, like all salts of fluorosilicic acid.
- Ammonium silicofluoride is a water insoluble silicon source for use in oxygen-sensitive applications, such as metal production.
- In extremely low concentrations (ppm), fluoride compounds are used in health applications.
- Fluoride compounds also have significant uses in synthetic organic chemistry.