Ingredient review
Calcium Sodium Borosilicate
INCI: CALCIUM SODIUM BOROSILICATE
A safe, non-reactive glass powder that adds visual appeal and texture to makeup without clogging pores.
In plain English
Calcium sodium borosilicate is a type of finely ground glass used in cosmetics to create shimmer, smooth texture, or opacity. It's the same family of materials used in heat-resistant glassware, but ground into a safe, inert powder for makeup. It doesn't absorb into skin or react with other ingredients, so it sits on the surface to provide visual effects.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Calcium Sodium Borosilicate is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Calcium Sodium Borosilicate.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A synthetic mineral compound made from calcium, sodium, boron, silicon, and oxygen, processed into a fine powder or microspheres. It is chemically inert and non-porous.
How it works
In a cosmetic product, it acts as a bulking agent or opacifier. Its glassy particles reflect light to create a luminous or pearlescent finish, and its smooth texture helps powders glide on evenly. It does not dissolve or interact with skin.
Pros
Safe for sensitive skin
Calcium sodium borosilicate is inert and rarely causes irritation or allergic reactions, making it suitable for most skin types.
Non-comedogenic shimmer
Unlike some mica or glitter, this ingredient does not clog pores or contribute to breakouts, so it's a good choice for acne-prone skin.
Cons and cautions
No skincare benefits
This ingredient is purely cosmetic—it doesn't hydrate, protect, or treat the skin. It's only for visual effect.
Potential grittiness
If the particle size is not finely milled, the powder can feel slightly gritty on the skin, especially in lip products.
Best for
- Anyone who wants a luminous finish in makeup
- Those with oily or acne-prone skin looking for non-comedogenic shimmer
Use caution if
- Those who prefer completely matte finishes
- Anyone with a known sensitivity to silicates (rare)
Usage tips
Safety summary
Calcium sodium borosilicate is considered safe for cosmetic use. It is non-irritating, non-sensitizing, and non-comedogenic. The main risk is inhalation of loose powder, which can irritate the lungs, so avoid creating airborne dust.
Research notes
The Cosmetic Ingredient Review (CIR) panel has evaluated calcium sodium borosilicate and found it safe for use in cosmetics at concentrations up to 10%. No significant toxicity or irritation was reported in studies.
Common label clues
- Typical concentration
- 1-10% in color cosmetics; lower in leave-on products
- Regulatory status
- Approved for use in cosmetics in the EU, US, and most major markets. Considered safe at typical concentrations by the Cosmetic Ingredient Review (CIR) panel.
- Common uses
- Nail polish, Lip gloss, Pressed powders, Eye shadow
- Environmental note
- Calcium sodium borosilicate is a synthetic mineral that does not biodegrade quickly, but it is not known to be bioaccumulative or toxic to aquatic life.
Good to know
- This ingredient is often used as a safer alternative to traditional glitter because it's biodegradable and non-toxic.
- It is also used in some sunscreens as a bulking agent.
Common questions
What is Calcium Sodium Borosilicate in beauty products?
Calcium sodium borosilicate is a type of finely ground glass used in cosmetics to create shimmer, smooth texture, or opacity. It's the same family of materials used in heat-resistant glassware, but ground into a safe, inert powder for makeup. It doesn't absorb into skin or react with other ingredients, so it sits on the surface to provide visual effects.
What does Calcium Sodium Borosilicate do in a beauty product?
In a cosmetic product, it acts as a bulking agent or opacifier. Its glassy particles reflect light to create a luminous or pearlescent finish, and its smooth texture helps powders glide on evenly. It does not dissolve or interact with skin.
Is Calcium Sodium Borosilicate safe for most people?
Calcium sodium borosilicate is considered safe for cosmetic use. It is non-irritating, non-sensitizing, and non-comedogenic. The main risk is inhalation of loose powder, which can irritate the lungs, so avoid creating airborne dust.
Who should be careful with Calcium Sodium Borosilicate?
Those who prefer completely matte finishes Anyone with a known sensitivity to silicates (rare)
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.