mineral

Quartz crystal fragment in weathered host rock

Quartz (SiO₂), possibly in a feldspathic or iron-stained matrix

AI-generated identification · may be incorrect

Small elongated, translucent-to-opaque crystal with a vitreous luster and whitish-gray to brown iron staining. Quartz has Mohs hardness 7, no cleavage, conchoidal fracture, and a trigonal crystal structure; the apparent prismatic form is consistent with quartz, though the image is insufficient for certainty.

Identified August 9, 2026More mineral →

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Physical properties

Formation & geological history

Likely formed in a hydrothermal vein or pegmatitic cavity, later weathered and iron-stained; precise age and locality cannot be determined visually. The brown coating may be limonite/goethite alteration.

Uses & applications

Quartz is used in glass, ceramics, engineered stone, electronics, abrasives, and jewelry; this small irregular specimen has mainly educational or collecting interest.

Geological facts

Quartz commonly forms six-sided prisms terminating in pyramidal faces, but weathering can obscure those features. A steel knife should not scratch fresh quartz, while quartz can scratch ordinary glass.

Field identification & locations

Common in quartz veins, pegmatites, granites, metamorphic rocks, and alluvial gravels worldwide. Confirm with a hardness test, streak (white), and closer inspection for hexagonal faces; matrix identity remains uncertain.