mineral

Quartz (Milky or Rough Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Off-white to pale yellow; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Off-white to pale yellow
Luster: Vitreous to greasy

Identified June 19, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Off-white to pale yellow; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed primarily from cooling magma or precipitation from hydrothermal veins. It is one of the most abundant minerals on Earth and can be found in rocks from virtually any geological era.

Uses & applications

Used in glassmaking, electronics (oscillators), abrasives, construction as aggregate, and as a semi-precious gemstone in jewelry when found in high quality.

Geological facts

Quartz is the source of the term 'crystal,' derived from the Greek word 'krystallos,' meaning ice, as ancient Greeks believed quartz was ice frozen so hard it would never melt.

Field identification & locations

Identify by its hardness (will scratch glass) and lack of cleavage. Commonly found in river beds, beaches, and mountainous outcrops globally.

Other mineral specimens

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

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