mineral

Quartz (Milky Quartz Pebble)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous (glassy) to greasy

Identified March 21, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. This specific specimen has been smoothed and rounded over thousands of years by fluvial or marine erosion (water action).

Uses & applications

Industrial use in glassmaking, abrasives, and electronics (piezoelectric properties). In this pebble form, primarily used for landscaping, decorative gravel, and lapidary tumbling for hobbyists.

Geological facts

Quartz is the second most abundant mineral in the Earth\'s continental crust. Pure quartz is clear; the white \'milky\' color of this specimen is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its ability to scratch glass (hardness) and the lack of cleavage planes. Found globally on beaches, riverbeds, and in soil. It is a primary indicator of granite environments.

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