mineral

Muscovite Mica (in Quartz matrix)

Potassium aluminum silicate hydroxide fluoride (KAl2(AlSi3O10)(F,OH)2)

Hardness: 2-2.5 on Mohs scale (mica) and 7 (quartz); Color: Silvery-white to pale tan; Luster: Pearly to metallic; Crystal Structure: Monoclinic; Cleavage: Perfect basal (peels into thin sheets); Specific Gravity: 2.76-3.0

Hardness: 2-2
Color: Silvery-white to pale tan
Luster: Pearly to metallic

Identified March 27, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed in igneous environments (pegmatites and granites) or metamorphic environments (schists and gneises). This specimen appears to be from a pegmatite where slow cooling allowed for large crystal formation.

Uses & applications

Used as an electrical insulator in capacitors/transistors, in heat-resistant windows (isnglass), as a filler in paints and plastics, and in cosmetics (glitter/shimmer).

Geological facts

Muscovite was historically used for window panes in Russia (the 'Muscovy region'), leading to its name. It is highly resistant to heat and chemicals, making it a critical industrial material.

Field identification & locations

Identify by its 'book' like structure that can be peeled into paper-thin, transparent sheets with a fingernail. Commonly found in mountainous regions with high metamorphic or granitic activity.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

mineral