metamorphic

Weathered quartz-rich rock, possibly quartzite or altered granite

Quartz-dominant silicate rock; exact identification requires a fresh surface and tests

AI-generated identification · may be incorrect

Hardness approximately 6–7 Mohs; mottled white, tan, and rusty brown, with dull to weakly vitreous luster and an irregular, massive texture. Brown coloration likely comes from iron-oxide staining; visible crystal structure is obscured by weathering.

Identified September 4, 2026More metamorphic →

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At a glance

Common name: Weathered quartz-rich rock, possibly quartzite or altered granite
Scientific name: Quartz-dominant silicate rock; exact identification requires a fresh surface and tests
Category: metamorphic
Identified: September 4, 2026
Method: Standard

AI Estimated Value

About $0–$10 for a common weathered specimen; up to $20–$50 if it proves unusually attractive, well-crystallized, or locally significant.

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 quartz-rich igneous or sedimentary material and later altered or metamorphosed, with surface oxidation during weathering. Geological age cannot be determined from the photograph.

Uses & applications

Unlikely to have commercial value in this weathered form; sound quartzite can be used as aggregate, building stone, or decorative rock, while attractive pieces may be collected.

Geological facts

The white areas may be quartz, feldspar, or weathered veins, so the specimen cannot be confidently named from appearance alone. A fresh broken edge, streak, acid reaction, and hardness test would improve identification.

Field identification & locations

Common in weathered outcrops and gravel deposits worldwide; quartz-rich material should scratch glass, while calcite-rich rock fizzes in dilute hydrochloric acid. Rusty brown surfaces indicate iron-bearing minerals oxidizing.