sedimentary or metamorphic

Rounded brown pebble, likely chert or iron-stained quartzite

Microcrystalline quartz (SiO₂), possibly quartzite; identification is uncertain from the image

AI-generated identification · may be incorrect

Dark brown, smooth and water-worn, with a dull-to-waxy luster and subtle granular texture. Quartz-rich material is typically Mohs 7, lacks cleavage, has conchoidal fracture, and specific gravity around 2.6–2.7.

Identified September 12, 2026More sedimentary or metamorphic →

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At a glance

Common name: Rounded brown pebble, likely chert or iron-stained quartzite
Scientific name: Microcrystalline quartz (SiO₂), possibly quartzite; identification is uncertain from the image
Category: sedimentary or metamorphic
Identified: September 12, 2026
Method: Standard

AI Estimated Value

About $1–$10 as a common tumbled or collected pebble; higher only if polished or unusually patterned.

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 formed from silica-rich sediment that became chert, or sandstone recrystallized into quartzite, later colored by iron oxides and rounded by stream or beach transport. Exact geological age and formation setting cannot be determined visually.

Uses & applications

Commonly used as aggregate, road material, landscaping stone, and occasionally as a lapidary or carving material; this small specimen has little commercial value.

Geological facts

Its compact, fine-grained appearance and brown coloration are consistent with iron-stained chert, but lighting and surface weathering obscure diagnostic details.

Field identification & locations

Look for a glassy or waxy surface, very high scratch resistance, no visible cleavage, and conchoidal fracture; it should scratch ordinary glass. Common in river gravels, beaches, and glacial deposits.