mineral

Likely milky quartz or white calcite

Quartz (SiO₂) or calcite (CaCO₃); identification is limited by the photograph

AI-generated identification · may be incorrect

Opaque to translucent white, vitreous to waxy luster, irregular fracture, and no obvious crystal faces. Quartz has Mohs hardness 7 and specific gravity 2.65; calcite has hardness 3, prominent rhombohedral cleavage, and specific gravity 2.71.

Identified September 6, 2026More mineral →

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Physical properties

Formation & geological history

Quartz commonly forms in hydrothermal veins and igneous or metamorphic rocks; calcite forms in limestone, veins, caves, and hydrothermal deposits. Ages range from recent precipitates to Precambrian rocks.

Uses & applications

Quartz is used in glass, electronics, abrasives, and ornamental specimens; calcite is used in cement, lime, aggregate, and optical specimens. Neither appears gem-grade from this image.

Geological facts

A steel nail or knife will not scratch quartz but can scratch calcite; dilute vinegar or hydrochloric acid fizzes on calcite but not quartz.

Field identification & locations

Common worldwide, including quartz veins and limestone regions. Test hardness and acid reaction; a definitive identification may require a fresh surface or lab testing.