mineral

Weathered quartz-rich rock fragment

Likely microcrystalline quartz with iron-oxide staining; exact identification is uncertain from the image

AI-generated identification · may be incorrect

Tan to brown, dull-to-waxy luster with small translucent crystalline areas; likely hardness about 7 Mohs, no obvious cleavage, and moderate-to-high specific gravity (~2.6). The granular texture may indicate quartzite, chert, or quartz vein material rather than a single crystal.

Identified September 16, 2026More mineral →

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Physical properties

Formation & geological history

Probably formed from silica-rich hydrothermal vein material or metamorphosed sandstone, then weathered and stained by iron oxides. Its geological age cannot be determined visually.

Uses & applications

Common quartz-rich material is used for glass, abrasives, aggregate, and decorative stone; this small fragment has negligible commercial or jewelry value.

Geological facts

Iron staining commonly produces yellow, tan, orange, and brown colors from limonite or goethite. A steel file should not easily scratch fresh quartz surfaces.

Field identification & locations

Look for glassy fracture, hardness, and lack of cleavage; vinegar is usually unreactive unless carbonate is present. Common in quartz veins, weathered outcrops, gravel, and metamorphic terrains.