metamorphic

Weathered quartz-rich metamorphic rock, likely quartzite

Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with feldspar, mica, and iron-oxide staining

AI-generated identification · may be incorrect

Hardness about 7 Mohs; pale gray to cream with rusty red-brown patches, dull to weakly vitreous luster, massive granular texture, and no obvious cleavage. The irregular rounded shape and weathered surface suggest natural abrasion and oxidation.

Identified September 19, 2026More metamorphic →

Explore Weathered quartz-rich metamorphic rock, likely quartzite 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: Weathered quartz-rich metamorphic rock, likely quartzite
Scientific name: Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with feldspar, mica, and iron-oxide staining
Category: metamorphic
Identified: September 19, 2026
Method: Standard

AI Estimated Value

About $1-$15 as a common field specimen; $20-$75 if unusually attractive, polished, or locality-documented.

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

Formed when quartz-rich sandstone was recrystallized under heat and pressure, commonly during regional mountain-building; its exact geological age cannot be determined from the photograph. It may represent a resistant glacial or stream-transported cobble.

Uses & applications

Used as crushed aggregate, road stone, building stone, and decorative facing; attractive pieces may be polished, though this specimen appears ordinary and unworked.

Geological facts

Quartzite commonly breaks across quartz grains rather than around them, making it tougher than sandstone. Iron oxides produce the reddish staining visible here.

Field identification & locations

Common in metamorphic terrains and glacial deposits. Test with a steel nail or glass: genuine quartzite resists scratching and can scratch glass; acid produces no reaction unless carbonate contamination is present.