metamorphic
Banded quartzite pebble
Quartzite, predominantly crystalline quartz (SiO₂), with darker accessory minerals
AI-generated identification · may be incorrectTypically Mohs hardness 7, gray to tan color, glassy to sugary luster, granular interlocking quartz texture, and no obvious cleavage. The specimen is rounded and polished naturally by abrasion, with a contrasting white quartz-rich vein or band.
Identified More metamorphic →
Explore Banded quartzite pebble in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Typically Mohs hardness 7, gray to tan color, glassy to sugary luster, granular interlocking quartz texture, and no obvious cleavage. The specimen is rounded and polished naturally by abrasion, with a contrasting white quartz-rich vein or band.
Formation & geological history
Formed when quartz-rich sandstone was recrystallized under heat and pressure, commonly during regional metamorphism; its precise geological age cannot be determined from the photograph. The vein likely formed when silica-rich fluids filled a fracture and later crystallized.
Uses & applications
Used as durable crushed stone, building stone, paving, countertops, and decorative aggregate; attractive pebbles are collected or used in landscaping. This small specimen has modest gem-market value.
Geological facts
Quartzite is harder and more resistant to weathering than its sandstone precursor, making it common in river gravels and resistant mountain ridges. A white vein can reflect later silica mineralization rather than original sedimentary layering.
Field identification & locations
Identify it by its very hard, glassy, sand-sized interlocking texture and inability to scratch easily with a steel knife; unlike sandstone, grains typically break through rather than separate around. Common in metamorphic belts and stream deposits worldwide.
More like this
