What it is
Hydrated silica is an amorphous form of silicon dioxide that contains bound water. In cosmetics it is valued for its natural absorbency and light-diffusing properties, helping soften the look of shine and texture, and it acts as the hard abrasive in toothpaste. Because it is a porous powder, it can take up oil and water, and it is also used to thicken products, suspend particles, and serve as an anti-caking agent.
Safety & warnings
Hydrated silica is an inert, amorphous mineral powder that sits on the skin surface and is used both as a gentle abrasive in toothpaste and as an absorbent in cosmetics. As an oil-absorbing material it can contribute to a drier, more matte feel, so people with very dry skin may prefer formulas where it is balanced with humectants and emollients.
Origin & sourcing
Hydrated silica can be manufactured or mined. Precipitated amorphous silica is produced by acidifying a silicate solution to form a gelatinous precipitate or silica gel, which is then washed and dehydrated to yield a colorless microporous silica.
Questions everyone asks
What is hydrated silica made from?
It is an amorphous form of silicon dioxide; the manufactured version is made by acidifying a silicate solution into a silica gel that is washed and dried.
Why is hydrated silica in sunscreen?
It is an absorbent, light-diffusing powder that helps absorb oil, reduce shine, and refine the look of the surface.
Is hydrated silica the same as silica gel?
Yes, the manufactured material is essentially a microporous amorphous silica, the same family as silica gel.