mineral

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 (Mohs scale); Color: White to off-white, translucent; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal system; Cleavage: None (conchoidal fracture).

Hardness: 7 (Mohs scale)
Color: White to off-white, translucent
Luster: Vitreous to waxy

Identified July 20, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to off-white, translucent; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal system; Cleavage: None (conchoidal fracture).

Formation & geological history

Forms in hydrothermal veins or as a primary constituent in igneous rocks like granite. This specific specimen has been water-worn into a rounded pebble shape through mechanical erosion in a river or coastal environment.

Uses & applications

Used in construction aggregate, as an abrasive, and in the manufacturing of glass and ceramics. Pure varieties are used in electronics for their piezoelectric properties.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by tiny fluid or gas inclusions trapped during the crystal's formation.

Field identification & locations

Identify by its hardness (it can scratch glass and steel) and lack of cleavage. Commonly found in riverbeds, beaches, and glacial deposits. Look for translucent white color and rounded surfaces.