sedimentary

Weathered quartz-rich sandstone or quartzite cobble

Quartz arenite sandstone; possibly weakly metamorphosed quartzite, composed mainly of SiO₂ (quartz)

AI-generated identification · may be incorrect

Hardness about 6–7; pale gray-beige, fine-grained, dull to slightly granular luster, massive structure, and no obvious cleavage. The rounded form and faint horizontal bands suggest water-worn bedding or compositional layering.

Identified September 12, 2026More sedimentary →

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At a glance

Common name: Weathered quartz-rich sandstone or quartzite cobble
Scientific name: Quartz arenite sandstone; possibly weakly metamorphosed quartzite, composed mainly of SiO₂ (quartz)
Category: sedimentary
Identified: September 12, 2026
Method: Standard

AI Estimated Value

Approximately $1–$15 as a common landscaping or field specimen; $20–$50 if unusually attractive, clearly identified, or locally collectible.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Likely lithified quartz-rich sand deposited in an ancient river, beach, or marine setting, later uplifted and rounded by erosion; age cannot be determined from the image. If quartzite, burial and metamorphism recrystallized the sandstone.

Uses & applications

Common sandstone is used for building stone, paving, aggregate, and landscaping; quartzite is used for durable countertops, roadstone, and decorative stone. This individual cobble has little commercial value.

Geological facts

Its smooth, elliptical shape indicates prolonged transport or mechanical weathering. The pale color reflects abundant quartz and limited dark iron-bearing minerals.

Field identification & locations

Common in stream gravels, glacial deposits, beaches, and landscaping beds. Test with a steel nail and inspect a fresh break: quartzite resists scratching and fractures across grains, while sandstone commonly breaks around visible sand grains.