What is Silica?

Silica is a broad term covering forms of silicon dioxide (SiO₂). In cosmetics and mineral makeup, you’ll typically encounter two main types:

• Crystalline silica — the form found in sand, quartz, masonry materials, etc. It has a structured crystal lattice.

• Amorphous silica (also called hydrated silica in many contexts) — non‑crystalline, often synthetically made or processed, lacking the rigid crystal lattice structure.

These types behave differently and have very different safety implications.

How Silica is Used in Mineral Makeup

Silica (especially the amorphous or hydrated forms) is used in makeup for a few useful functions:

• Oil and moisture absorption — helps reduce shine and keep makeup in place for people with oily skin.

• Anti‑caking / bulking agent — helps powders flow smoothly and prevents clumping.

• Light diffusion / blurring — small silica particles can soften the appearance of fine lines or skin texture by scattering light.

So in formulations, silica helps with matte finish, smoother application, and overall better texture.

Safety Concerns & What Type Matters

The key to understanding whether silica is safe in mineral makeup lies in which form of silica is used, how it’s processed, how fine the particles are, and how the product is applied.

Crystalline Silica — more problematic

• This is the form found in many industrial settings (sandblasting, mining, masonry). Inhaled in dust form, it can cause significant lung issues: inflammation, scarring (fibrosis), and diseases such as silicosis. It is also classified as a potential carcinogen when inhaled in certain circumstances.

• Cosmetic products should not contain crystalline silica. If a product did, that would be cause for concern.

Amorphous Silica / Hydrated Silica — generally safer

• This is the kind typically used in cosmetics. It’s non‑crystalline, milder, and much less likely to cause the kinds of lung or chronic tissue damage associated with crystalline silica.

• It still may have the downside of being mildly abrasive, drying, or irritating — especially for certain skin types (e.g. dry or mature skin) or if used in high proportions.

Why Some Manufacturers Avoid Silica

Even though many forms of silica are considered safe when used properly, there are reasons why some brands choose not to include it, or prefer other ingredients in place of silica:

1. Potential for irritation or dryness — Because silica absorbs moisture (good for oil control), it can over‑dry skin that’s already dry, or cause discomfort over time if the skin barrier is compromised.

2. Vague labeling / potential confusion — Sometimes ingredient lists just say “silica” without clarifying which form (crystalline vs amorphous, hydrated vs other). That can cause worry among consumers who associate “silica” with the more hazardous crystalline form.

3. Feel & finish trade‑off — For some skin types, or aesthetically, silica’s texture might make makeup feel or look more matte or less “luminous.” Brands that want a more dewy or soft finish may prefer other ingredients.

4. Consumer perception / “clean beauty” trends — As consumers become more aware / cautious about ingredients, some brands avoid including ingredients that might be considered controversial or misunderstood — even if in safe form — just to appeal to sensitive‑skin consumers or those favoring more minimal ingredient lists.

Regulatory and Scientific Consensus

• The Cosmetic Ingredient Review (CIR), which reviews cosmetic safety, has assessed several silica and silicate ingredients. They concluded that amorphous / hydrated silica (and related silicates) are safe when used in cosmetics in normal concentrations, given they are formulated to avoid irritation.

• One caveat: there is less data on some uses — for example for airbrush makeup (which can lead to inhalation of very fine particles). CIR notes that inhalation exposure can increase risk if formulations are dusty or if crystalline silica is present in even small trace amounts.

What to Look for If You’re Concerned

If you’re shopping for mineral makeup and are wary about silica, here are some things to check / ask:

• Does the label specify “amorphous silica” or “hydrated silica” vs just “silica”?

• What is the position of silica in the ingredient list? If it’s high up, the product has a higher proportion, which might increase possibility of dryness or irritation.

• How does the product feel on your skin? Does it dry you out or settle into fine lines?

• Do you have a skin type that’s more sensitive or dry? If yes, you might want products with a lower silica content, or that use other “blurring” or anti‑caking agents.

• Use products as intended. For example, avoid inhaling loose powders, use brushes gently, avoid applying a lot of dust onto sensitive or broken skin.

Bottom Line

Silica isn’t inherently bad. Amorphous / hydrated silica, when properly processed and used in reasonable amounts, is widely considered safe in mineral makeup. Its benefits — oil‑control, anti‑caking, light diffusion — are real. But not all “silica” is the same, and there are trade‑offs, especially for skin that’s dry, sensitive, or mature.

Choosing makeup that discloses what kind of silica is used, testing how it feels on your skin, and balancing finish with comfort are good strategies, which is why I love Sterling Minerals

 makeup (no affiliation).