Mineral

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on the Mohs scale. Color: Colorless (clear) as seen, but can also be milky white, smoky, purple (amethyst), yellow (citrine), pink (rose quartz), etc., depending on impurities. Luster: Vitreous (glassy). Crystal Structure: Hexagonal system. Cleavage: None (fractures conchoidally). Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Luster: Vitreous (glassy)

Identified August 25, 2025More mineral →

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Physical properties

Formation & geological history

Clear quartz forms from the crystallization of silicon dioxide (SiO2) in various geological environments. It can crystallize directly from magma (igneous), be formed through hydrothermal processes (hot water solutions often associated with igneous intrusions), or grow as a secondary mineral in sedimentary rocks and veins. Its geological age varies widely, from very ancient Precambrian formations to relatively recent deposits.

Uses & applications

In industry, quartz is used in electronics (oscillators, filters, frequency control), glass manufacturing, abrasives, and as a raw material for silicon production. In jewelry, clear quartz is faceted into gemstones, beads (as seen in the image), and carved into ornamental objects. It is also collected by mineral enthusiasts for its crystal habits and clarity.

Geological facts

Quartz is one of the most common minerals on Earth's crust, found in a wide range of igneous, metamorphic, and sedimentary rocks. Its piezoelectric properties (generating an electric charge when mechanically stressed) make it essential in electronics for oscillators, watches, and radio transmitters. "Crystal healing" practices often utilize clear quartz, believing it amplifies energy and thought.

Field identification & locations

Clear quartz is identified by its glass-like luster, hardness (it can scratch glass and steel), conchoidal fracture (shell-like breaks), and often by its hexagonal prism crystal habit with pyramidal terminations when found in its natural form. It's commonly found in pegmatites, granites, sandstone, and various metamorphic rocks, as well as in hydrothermal veins. To distinguish from glass, quartz will usually feel colder to the touch (higher thermal conductivity) and cannot be scratched by steel.

Other mineral specimens

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Mineral Sand (Heavy Mineral Sand Concentrate)

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

mineral

Calcite–fluorite mineral specimen with iron-oxide staining

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

mineral

Soil with Mineral Detritus and Quartz Fragments

Regolith / Silicate Mineral Aggregate

sedimentary

Septarian Pebble

Septarian nodule / Concretion

sedimentary

Schist

Metamorphic