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Mineral group · Silicate

Mica

XY₂₋₃Z₄O₁₀(OH,F)₂

Sheet silicates splitting into paper-thin flakes — muscovite, biotite, lepidolite.

Hardness2–3
Crystal systemMonoclinic
ClassSilicate
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Mica specimen

A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical pr — Photo: James St. John · CC BY 2.0

Mica

Also known as: Mica group, Isinglass.

The sheet silicates — minerals that split into thin, elastic, transparent flakes; muscovite and biotite are the best-known members.

Intro adapted from Wikipedia (CC BY-SA).

Mica is a mineral group, with the chemical formula XY₂₋₃Z₄O₁₀(OH,F)₂.

It crystallizes in the monoclinic crystal system.

Key properties: Mohs hardness 2–3; typically colorless or brown or green or purple or gray.

Collections: Everyday Minerals.

Index entry. This entry combines official IMA/RRUFF species data with published physical-property data and a Wikipedia introduction — a full written entry hasn’t been published yet. Browse more M minerals or help write this entry.