metamorphic

Banded ironstone (likely iron-rich metamorphic rock)

Ferruginous quartzite or ironstone; exact identification requires examination of a fresh surface

AI-generated identification · may be incorrect

Rust-brown and gray, with elongated bands and a dull to slightly silky luster. Likely composed mainly of quartz and iron oxides; hardness is typically about 6–7 Mohs, though the pictured weathered piece may be softer at the surface.

Identified September 26, 2026More metamorphic →

Explore Banded ironstone (likely iron-rich metamorphic rock) 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: Banded ironstone (likely iron-rich metamorphic rock)
Scientific name: Ferruginous quartzite or ironstone; exact identification requires examination of a fresh surface
Category: metamorphic
Identified: September 26, 2026
Method: Standard

AI Estimated Value

About $1–$10 for a small common rough specimen; higher value requires confirmed provenance or distinctive banding.

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

Iron-rich sediments were compacted and later recrystallized or altered by heat and pressure; iron oxidation produces the rusty bands. Such rocks formed in many geological periods, so age cannot be determined from the image.

Uses & applications

Used as iron ore where iron content is high, and as decorative or collectible stone; this small rough piece has no evident commercial use.

Geological facts

Banded iron formations preserve evidence of ancient oceans and changes in Earth’s early atmosphere, though this specimen’s specific origin cannot be established visually.

Field identification & locations

Look for persistent alternating iron-rich reddish-brown and silica-rich gray bands, plus a notably hard surface; test a fresh edge and streak before confirming. Banded ironstone occurs worldwide, including Australia, South Africa, and North America.