metamorphic

Tumbled quartz-rich stone, likely quartzite

Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with feldspar or iron-oxide impurities

AI-generated identification · may be incorrect

Hardness about 7 Mohs; tan to brown, opaque, with a dull to slightly glassy luster and sugary granular texture. Massive, nonfoliated, and lacks obvious cleavage; iron staining produces the warm coloration.

Identified September 3, 2026More metamorphic →

Explore Tumbled quartz-rich stone, 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: Tumbled quartz-rich stone, likely quartzite
Scientific name: Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with feldspar or iron-oxide impurities
Category: metamorphic
Identified: September 3, 2026
Method: Standard

AI Estimated Value

$2–$15 as a common tumbled specimen; approximately $10–$40 if sold as an attractive polished decorative stone.

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 metamorphosed under heat and pressure, recrystallizing its grains into interlocking quartz. Quartzite commonly formed during Precambrian to younger mountain-building events, though this individual’s age cannot be determined visually.

Uses & applications

Used as crushed aggregate, road stone, building stone, landscaping material, and decorative tumbled stone; generally low jewelry value unless unusually attractive or patterned.

Geological facts

Quartzite is typically harder and more resistant to weathering than its sandstone precursor. The specimen’s smooth rounded shape indicates river wear or tumbling rather than its original geological form.

Field identification & locations

Identify it by its hardness, granular quartz texture, lack of visible bedding, and resistance to scratching by ordinary steel; it should scratch glass. Common in mountain belts, river gravels, and glacial deposits.