Ingredient review
Calcium Sulfate Hydrate
INCI: CALCIUM SULFATE HYDRATE
Calcium Sulfate Hydrate is a safe, mineral-based ingredient used to add texture, opacity, or absorbency in powder cosmetics, but it offers no active skincare benefits.
In plain English
Calcium Sulfate Hydrate is a naturally occurring mineral (also known as gypsum) that is ground into a fine powder for use in cosmetics. In skincare and makeup, it helps give products a smooth, silky feel, makes them less transparent, or soaks up excess oil. Think of it as a helper ingredient that improves the texture and performance of powders, masks, and foundations without directly treating your skin.
Review score
Safety, usefulness, and evidence
Useful in the right context, but not low-maintenance
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
- natural
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Read the cautions before using
Calcium Sulfate Hydrate 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 Sulfate Hydrate.
- 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
Calcium Sulfate Hydrate is the hydrated form of calcium sulfate, a mineral salt. In cosmetics, it appears as a white or off-white powder that is insoluble in water. It is mined from natural deposits or produced synthetically, and it is the same mineral used in plaster of Paris, though cosmetic grades are purified for safety.
How it works
In a cosmetic product, Calcium Sulfate Hydrate acts as a bulking agent (adds volume and body), an opacifying agent (reduces transparency), and an absorbent (soaks up moisture or oil). When included in a powder or mask, it helps the product feel smooth on the skin, improves its spreadability, and can help control shine by absorbing sebum.
Pros
Safe and non-irritating
Calcium Sulfate Hydrate has a low irritation and comedogenic risk, making it suitable for sensitive skin types when used in typical concentrations.
Improves product feel
It gives powders a smooth, silky texture that glides onto the skin, enhancing the user experience without adding stickiness.
Cons and cautions
No active benefits
Unlike ingredients like hyaluronic acid or niacinamide, Calcium Sulfate Hydrate does not hydrate, brighten, or treat skin concerns—it only modifies texture.
Can be drying in high amounts
Because it absorbs oil and moisture, products with a high concentration may leave dry or dehydrated skin feeling tight or parched.
Best for
- People with oily or combination skin who want a matte finish
- Anyone using powder cosmetics and looking for a safe, non-irritating texturizer
Use caution if
- Those with very dry or flaky skin may find products with high amounts of this ingredient too drying
Usage tips
Safety summary
Calcium Sulfate Hydrate is considered safe for topical cosmetic use. It has low irritation and comedogenic potential, and no significant toxicity concerns when used as intended. However, inhalation of loose powder should be avoided, and individuals with very dry skin may find it slightly drying.
Research notes
Research on Calcium Sulfate Hydrate in cosmetics is limited, but it has a long history of safe use in personal care products. The Cosmetic Ingredient Review (CIR) panel has evaluated related calcium salts and found them safe. No peer-reviewed studies indicate significant skin irritation or sensitization at typical cosmetic levels.
Common label clues
- Typical concentration
- Typically 1–10% in powder products, varies by formulation
- Regulatory status
- Calcium Sulfate Hydrate is generally recognized as safe for use in cosmetics by the U.S. FDA and is listed in the EU CosIng database. It is not restricted in concentration, but manufacturers must ensure it is free from asbestos contamination (a concern with some natural talc sources).
- Common uses
- Face powders, Pressed powders, Masks, Foundations
- Environmental note
- Calcium Sulfate Hydrate is mined from natural gypsum deposits, which is a relatively abundant mineral. Mining can have local environmental impacts, but the ingredient itself is not considered harmful to aquatic ecosystems at typical cosmetic use levels.
Good to know
- Calcium Sulfate Hydrate is the same mineral as gypsum, but cosmetic grades are purified to remove impurities.
- It is often used in combination with other powders like talc or silica to balance texture and absorption.
- This ingredient is not water-soluble, so it is rarely found in serums, creams, or lotions.
Common questions
What is Calcium Sulfate Hydrate in beauty products?
Calcium Sulfate Hydrate is a naturally occurring mineral (also known as gypsum) that is ground into a fine powder for use in cosmetics. In skincare and makeup, it helps give products a smooth, silky feel, makes them less transparent, or soaks up excess oil. Think of it as a helper ingredient that improves the texture and performance of powders, masks, and foundations without directly treating your skin.
What does Calcium Sulfate Hydrate do in a beauty product?
In a cosmetic product, Calcium Sulfate Hydrate acts as a bulking agent (adds volume and body), an opacifying agent (reduces transparency), and an absorbent (soaks up moisture or oil). When included in a powder or mask, it helps the product feel smooth on the skin, improves its spreadability, and can help control shine by absorbing sebum.
Is Calcium Sulfate Hydrate safe for most people?
Calcium Sulfate Hydrate is considered safe for topical cosmetic use. It has low irritation and comedogenic potential, and no significant toxicity concerns when used as intended. However, inhalation of loose powder should be avoided, and individuals with very dry skin may find it slightly drying.
Who should be careful with Calcium Sulfate Hydrate?
Those with very dry or flaky skin may find products with high amounts of this ingredient too drying
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.