metamorphic
Quartzite Pebble
Quartzite (mostly SiO2)
Hardness: 7 on Mohs scale; Color: yellowish-white to cream; Luster: vitreous to dull; Crystal structure: granular/interlocking; Cleavage: none; Specific gravity: approx. 2.65
- Hardness
- 7 on Mohs scale
- Color
- yellowish-white to cream
- Luster
- vitreous to dull
Identified More metamorphic →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 on Mohs scale; Color: yellowish-white to cream; Luster: vitreous to dull; Crystal structure: granular/interlocking; Cleavage: none; Specific gravity: approx. 2.65
Formation & geological history
Formed via the metamorphism of quartz-rich sandstone under intense heat and pressure, causing quartz grains to recrystallize into a dense, interlocking mosaic of crystals.
Uses & applications
Used as construction aggregate, railway ballast, decorative landscaping stone, and occasionally in glassmaking if rare purity is met.
Geological facts
Quartzite is so tough that it often survives transport in rivers much longer than the stones it originated from; it will break through the quartz grains rather than around them like sandstone.
Field identification & locations
Identify by its extreme hardness (scratches glass) and sugary, granular texture; commonly found in riverbeds and glacial deposits as rounded cobbles.
More like this
