mineral

Milky quartz (tumbled quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; white to translucent, vitreous-to-waxy luster, usually massive rather than visibly crystalline, with conchoidal fracture and no cleavage. Specific gravity is about 2.65.

Identified September 12, 2026More mineral →

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Physical properties

Hardness 7 Mohs; white to translucent, vitreous-to-waxy luster, usually massive rather than visibly crystalline, with conchoidal fracture and no cleavage. Specific gravity is about 2.65.

Formation & geological history

Forms when silica-rich fluids crystallize in veins, cavities, and igneous or metamorphic rocks; its cloudy appearance comes from microscopic fluid inclusions or fractures. Quartz is widespread from Precambrian to modern geological settings.

Uses & applications

Used for ornamental stones, carvings, countertops, glass, ceramics, and electronics; attractive translucent pieces are sold as inexpensive cabochons or tumbled stones.

Geological facts

Quartz is one of Earth’s most abundant minerals and is piezoelectric, generating an electrical charge when stressed.

Field identification & locations

Identify by its glassy appearance, lack of cleavage, conchoidal fracture, and ability to scratch ordinary glass; milky quartz commonly occurs in hydrothermal veins worldwide. This specimen appears polished or tumbled.