mineral

Milky quartz (rough quartz fragment)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Typically Mohs hardness 7, vitreous to waxy luster, white to translucent coloration, and no cleavage; it shows irregular or conchoidal fracture and a trigonal crystal structure. The yellow-brown surface likely reflects iron-oxide staining or weathering.

Identified August 28, 2026More mineral →

Explore Milky quartz (rough quartz fragment) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Forms when silica-rich fluids crystallize in veins, cavities, or igneous and metamorphic rocks; individual specimens may range from Precambrian to recent geological settings. This fragment is too weathered and irregular to determine a precise locality or age.

Uses & applications

Used in glass, ceramics, abrasives, foundry materials, electronics, and engineered stone; attractive translucent pieces are used decoratively or as inexpensive specimens. It is generally low-value unless exceptionally clear, well-formed, or unusually colored.

Geological facts

Quartz is one of Earth’s most abundant minerals and is a major component of granite, sandstone, and many hydrothermal veins. The specimen’s translucent white body and hardness are consistent with quartz, though a simple glass-scratch test is not definitive.

Field identification & locations

Common worldwide, especially in hydrothermal veins and quartz-rich igneous or metamorphic terrains; test whether it scratches ordinary glass and inspect for conchoidal fracture. Avoid confusing it with calcite, which is softer and reacts readily with dilute acid.