Mica

What it is

Mica is a group of layered silicate minerals that split into extremely thin, flexible flakes. Those flakes reflect light, which is why mica gives a pearly shimmer and a soft-focus finish. It is used both on its own and as the substrate for coated pearlescent pigments, where a thin layer of titanium dioxide or iron oxide is deposited on the flake to create colour-shifting effects.

What it does well

• Softens the look of the skin by scattering light

  The flakes diffuse reflected light, which visually blurs texture and fine lines while the product is on. The effect is optical and disappears when the product is removed.

  Moderate evidence

Worth knowing

• Loose mica powder should not be inhaled

  As with other mineral powders, breathing in airborne dust is worth avoiding, which is a handling issue for loose products rather than for a wet mask.

  Matters most toUsers of loose shimmer powders.

• Sourcing rather than safety is the live issue

  Child labour in natural mica mining, particularly in parts of India and Madagascar, is a documented supply-chain problem. It is an ethical concern rather than a skin-safety one, and some brands respond by using synthetic fluorphlogopite instead.

  Matters most toBuyers who factor supply-chain ethics into purchasing decisions.

Where the EU stands