mineral

Grey Quartz (likely Smoky Quartz or Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: Translucent grey to beige, Luster: Vitreous/glassy, Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified April 28, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Translucent grey to beige, Luster: Vitreous/glassy, Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of environments, most commonly in igneous rocks like granite or in hydrothermal veins. Its grey color can be the result of natural irradiation (smoky quartz) or microscopic fluid inclusions (milky quartz).

Uses & applications

Used in gemstone collecting, metaphysical healing practices, glassmaking, and electronics (due to piezoelectric properties). This specific piece appears to be a polished 'palm stone' for meditation or decoration.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Specimens like this have been used as tools since the Stone Age due to their hardness and ability to produce sharp edges when broken.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and glassy appearance. It is found globally in riverbeds, mountains, and mines.

Other mineral specimens

See all

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