Science
Mechanism of Action
Chalk functions as a physical absorbent, drawing excess sebum and moisture into its structure to neutralize shine. In specialized carboxy-therapy applications, it reacts with acidic catalysts to release Carbon Dioxide (CO2), inducing the Bohr effect which temporarily boosts peripheral microcirculation and localized tissue oxygenation.
Research
Clinical Evidence
High confidence10%
Key findings
- 01 Modified surface-reacted calcium carbonate effectively blurs fine lines and provides a natural mattifying effect.
- 02 Safety assessments validated zero significant irritation or sensitization at high-load leave-on concentrations.
Transparency
Dusting Analysis
While often used as a bulking agent, Chalk requires a concentration of at least 3% to provide meaningful mattifying or blurring benefits. Percentages below 1% in active skincare are likely used for pH buffering or as a processing aid rather than for clinical skin benefits.
The Formula
Formulation
Stability
Highly stable in alkaline environments; however, it is reactive in acidic media (pH < 7), where it decomposes into calcium salts and CO2 gas.
Synergies
- Acidic compounds (for effervescent CO2 release)
- Clays
- Mineral pigments
Conflicts
- Strong acids
- Fluoride ions
- Phosphorous compounds
- Ammonium salts
Safety
Safety Profile
Generally Recognized As Safe (GRAS) by the FDA; however, its use is restricted in the eye area in the United States when utilized specifically as a color additive (CI 77220).
Your Skin
Skin Compatibility
Our Assessment
Verdict
An excellent, non-irritating mineral for sebum control and optical blurring in oily and combination skin protocols.
Related
Similar Ingredients
Finding similar ingredients…