mineral

Milky quartz (likely iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; white to pale honey-yellow, translucent, with a glassy to waxy luster. It has a hexagonal crystal structure and no true cleavage, breaking with conchoidal fractures; yellow coloration likely reflects iron staining or inclusions.

Identified August 15, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids crystallize in veins, cavities, and fractures of igneous or metamorphic rocks. Quartz is abundant from Precambrian to modern geological settings; the specimen’s exact age and locality cannot be determined visually.

Uses & applications

Common quartz is used in glass, ceramics, abrasives, electronics, and engineered stone; attractive pieces are sold as inexpensive mineral specimens. This rough fragment has modest decorative and collecting value.

Geological facts

Quartz is one of Earth’s most abundant minerals and is piezoelectric, generating an electrical charge under pressure. Its apparent translucency and irregular fracture distinguish it from calcite, which is softer and commonly cleaves into rhombohedra.

Field identification & locations

Likely quartz if it scratches glass or steel and does not scratch easily with a steel blade; it should not fizz in dilute hydrochloric acid. Common worldwide, especially in hydrothermal veins and granite-associated pegmatites.