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Mica

Silicate Minerals

A group of sheet silicate minerals that split into thin, flexible, glittering layers. It is the flecked shine in granite and gneiss, and the third of the three common minerals, with quartz and feldspar, that give granite its speckled texture. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Classification
Crystal System
Monoclinic 1
Classification
Silicate Mineral 1
Use
Industrial and Abrasive 2
Wikipedia 'Mica' states this use (or use-bearing statement); earth5 pass.
Kind
Mineral 3
Formation Class
Sheet silicate (phyllosilicate) 3
Chemical Formula
X2Y4-6Z8O20(OH,F)4 (general mica-group formula) 1
Hardness (Mohs)
2.5 3
Connections

Associated With

Granite, Materials

Granite's own lead description names mica as one of its main constituent minerals.

Source Granite (Wikipedia)
Pegmatite, Materials

Mica named as one of the three dominant minerals of most pegmatites.

Source Pegmatite (Wikipedia)
Schist, Materials

Mica-rich schist (mica schist) is one of the most common schist varieties.

Source Schist (Wikipedia)

Classified As

Entity-backed identity for the material classification this material already carries as an enum fact, pointing at the class subcategory of the same name. The enum fact itself stays on the entity unchanged.

Crystallizes In System

Entity-backed identity for the crystal-system enum value this material already carries, resolved to an earth concept by an explicit value-to-entity map (phase 3 bucket conversion, docs\design_entity_backed_browse_buckets_20260928.md). The crystal-system fact itself stays on the material unchanged.

In Discipline

Source Mineral (Wikipedia)
Sources
1. Mica (Wikipedia)
Wikimedia Foundation
  • Classification section
    X2Y4-6Z8[O]20([OH],[F])4
  • Entity classification (SubLabel)
    A group of sheet silicate minerals that split into thin, flexible, glittering layers. It is the flecked shine in granite and gneiss, and the third of the three common minerals, with quartz and feldspa
  • Mica (Wikipedia), body text
    All crystallize in the monoclinic system, with a tendency towards pseudohexagonal crystals
View the Source
2. Wikidata: Mica
Wikidata Q114675
Quote, Wikidata Q114675
P279 subclass chain verified to reach rock (Q8063) or mineral (Q7946) within a few hops; identified via Wikipedia pageprops (article title match), PlaybookNote 38526.
3. Mineral (Wikipedia)
Wikimedia FoundationView the Source
Granite (Wikipedia)
Wikimedia FoundationAssociated With: Granite, Lead section
Quote, Associated With: Granite, Lead section
is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, mica and plagioclase.
View the Source
Pegmatite (Wikipedia)
Wikimedia FoundationAssociated With: Pegmatite, Lead section
Quote, Associated With: Pegmatite, Lead section
Most pegmatites are composed of quartz, feldspar, and mica, having a similar silicic composition to granite.
View the Source
Schist (Wikipedia)
Wikimedia FoundationAssociated With: Schist, Body, protolith section
Quote, Associated With: Schist, Body, protolith section
Schist metamorphosed from mudstone is particularly common and is often very rich in mica (a mica schist).
View the Source
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