mineral

Quartz

Silicon dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness of 7 on the Mohs scale, typically clear to milky white or slightly yellow, vitreous luster, hexagonal crystal system, no cleavage, specific gravity of 2.65.

Identified August 31, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, typically clear to milky white or slightly yellow, vitreous luster, hexagonal crystal system, no cleavage, specific gravity of 2.65.

Formation & geological history

Forms in igneous, metamorphic, and sedimentary rocks from silica-rich solutions or melts. Common in pegmatites and hydrothermal veins.

Uses & applications

Used in glassmaking, electronics (oscillators), jewelry (often as semiprecious stones like amethyst or citrine), and as an abrasive.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its piezoelectric properties make it essential for clocks and watches.

Field identification & locations

Identified by its hardness (scratches glass), conchoidal fracture, and lack of cleavage. Very common worldwide.

Other mineral specimens

See all

Gneiss or Schist

Gneiss or Mica Schist with Garnet

Metamorphic

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Calcite–fluorite mineral specimen with iron-oxide staining

Calcite (CaCO₃), likely fluorite (CaF₂), with possible quartz and iron/manganese oxides

mineral

Septarian Pebble

Septarian nodule / Concretion

sedimentary

Mineral Sand (Heavy Mineral Sand Concentrate)

Placer deposit concentrate containing minerals such as ilmenite, rutile, zircon, and magnetite

mineral

Epidote

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

metamorphic