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Iron Oxides

Iron Oxides · CI 77491 · CI 77492 · CI 77499 · Iron Oxides (CI 77491) · Iron Oxides (CI 77492) · Iron Oxides (CI 77499)SPF filter

Mineral pigment that blocks visible light. Critical for melasma + post-inflammatory hyperpigmentation routines.

What it does

Iron oxides are the tinting pigments in mineral and tinted sunscreens (the red, yellow, and black variants). Beyond color, they absorb visible light — including the high-energy blue light from screens — that pure zinc or titanium dioxide does not block well. For melasma, post-inflammatory hyperpigmentation, and any condition driven by visible-light exposure, a tinted SPF is meaningfully more protective than an untinted one.

The evidence, graded

expert consensusMelasma is hormonally driven and worsened by UV exposure, visible light, heat, and friction. Iron-oxide-tinted mineral SPF + heat avoidance + gentle handling are foundational; ingredient treatments (hydroquinone, tranexamic acid, azelaic acid) work secondarily.Sarkar 2014 · Indian Dermatology Online Journal ↗

Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.

Also known as

ci 77491, ci 77492, ci 77499

Pairs worth knowing

Zinc Oxide (sunscreen) · works together ↗Titanium Dioxide · works together ↗Niacinamide (Vitamin B3) · works together ↗Tranexamic Acid · works together ↗

Read more

How Drop works · 5 minSunscreen Reapplication: Why Every 2 Hours Actually MattersSunscreen wears off faster than most people realize. What happens in those 2 hours, when reapplication matters most, and how to do it over makeup.

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