metamorphic
Quartzite pebble
Quartzite (SiO2)
Hardness: 7 (Mohs), Color: Off-white to light gray, Luster: Vitreous to dull, Crystal structure: Trigonal (microcrystalline), Cleavage: Indistinct/conchoidal fracture, Specific gravity: 2.6-2.65.
Identified More metamorphic →
Explore Quartzite pebble in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 (Mohs), Color: Off-white to light gray, Luster: Vitreous to dull, Crystal structure: Trigonal (microcrystalline), Cleavage: Indistinct/conchoidal fracture, Specific gravity: 2.6-2.65.
Formation & geological history
Formed from the metamorphism of quartz sandstone under high heat and pressure, causing quartz grains to recrystallize and fuse together. Typically found in mountain belts and river beds.
Uses & applications
Used in construction, road ballast, as a high-purity silica source in industry, and occasionally as decorative landscaping stones.
Geological facts
Quartzite is one of the toughest common stones and is resistant to chemical weathering. It is so hard that it can scratch steel and glass easily.
Field identification & locations
Identify by its hardness (scratches glass) and its granular, sugary texture on fresh breaks. This specimen appears water-worn into a disk or pebble shape, common in river or coastal environments.
More like this
