metamorphic

Quartz-rich metamorphic rock (likely quartzite)

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

AI-generated identification · may be incorrect

Hardness about 7 Mohs; white to gray and rusty brown, with a vitreous to sugary sparkle. Massive, granular texture and no obvious cleavage; quartz grains commonly fracture unevenly, with specific gravity near 2.65.

Identified September 20, 2026More metamorphic →

Explore 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: Quartz-rich metamorphic rock (likely quartzite)
Scientific name: Quartzite; predominantly microcrystalline quartz (SiO₂), with probable iron-oxide staining and minor feldspar/mica
Category: metamorphic
Identified: September 20, 2026
Method: Standard

AI Estimated Value

Typically $5–$25 for a hand specimen; roughly $25–$100 if unusually colorful, crystal-rich, or attractively shaped.

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 recrystallized under heat and pressure during regional metamorphism, welding the grains together; its exact geological age cannot be determined from the image. Rust-colored areas likely represent weathered hematite or goethite.

Uses & applications

Used as crushed stone, road aggregate, building stone, and decorative facing; attractive specimens are collected but are generally low-value.

Geological facts

Quartzite is typically harder and more resistant to weathering than its sandstone precursor, and broken surfaces often show grains continuing across the fracture rather than separating along bedding.

Field identification & locations

Identify it by a quartz-rich, sugary texture and testing whether it scratches glass; unlike sandstone, it usually breaks through grains. Common in metamorphic mountain belts worldwide, including the Appalachians, Rocky Mountains, Alps, and many Precambrian shields.