sedimentary

Likely weathered sandstone or iron-rich chert fragment

Indeterminate; probable quartz-rich sandstone (SiO₂) with iron-oxide cement, possibly chert

AI-generated identification · may be incorrect

Brown to reddish-brown, dull to subtly granular surface, irregularly rounded and elongated. Likely hardness about 6–7 Mohs if quartz-rich; no visible cleavage, with earthy to weakly vitreous luster and moderate density.

Identified August 11, 2026More sedimentary →

Explore Likely weathered sandstone or iron-rich chert fragment in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

At a glance

Common name: Likely weathered sandstone or iron-rich chert fragment
Scientific name: Indeterminate; probable quartz-rich sandstone (SiO₂) with iron-oxide cement, possibly chert
Category: sedimentary
Identified: August 11, 2026
Method: Standard

AI Estimated Value

Generally $0–$5 as an ordinary loose specimen; up to about $10–$20 if locally significant, unusually patterned, or sold as a labeled geological sample.

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

Most consistent with a naturally weathered sedimentary fragment formed by cementation of sand-sized quartz grains, with iron oxides producing the brown color; geological age cannot be determined from the image. If chert, it formed from microcrystalline silica replacing or accumulating in sediment.

Uses & applications

Common sandstone is used for building stone, paving, aggregate, and landscaping; chert is used mainly as aggregate and occasionally for tools or collecting. This small, unverified specimen has minimal commercial value.

Geological facts

The image does not show diagnostic crystals, bedding, or fracture surfaces, so exact identification is uncertain. A streak, hardness, and magnified-grain test would distinguish sandstone from chert and iron-rich volcanic rocks.

Field identification & locations

Likely sources include weathered sedimentary outcrops, river gravels, beaches, and glacial deposits. Check whether it scratches glass, leaves a reddish-brown streak, and shows visible sand grains or a smooth waxy fracture.