metamorphic
Quartzite Pebble
Quartzite (SiO2)
Hardness: 7 on Mohs scale; Color: Tan to light brown; Luster: Vitreous to waxy; Crystal structure: Hexagonal (microcrystalline); Cleavage: None; Specific gravity: 2.63 - 2.65
- Hardness
- 7 on Mohs scale
- Color
- Tan to light brown
- Luster
- Vitreous to waxy
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: Tan to light brown; Luster: Vitreous to waxy; Crystal structure: Hexagonal (microcrystalline); Cleavage: None; Specific gravity: 2.63 - 2.65
Formation & geological history
Formed from the metamorphism of quartz sandstone under high heat and pressure. This specimen shows significant rounding due to water erosion, likely from a river or beach environment.
Uses & applications
Used in construction as road ballast, in glass making (if high purity), and in jewelry as tumbled stones or lapidary art.
Geological facts
Quartzite is so tough that it often outlasts the surrounding rocks during erosion, forming ridges and mountain peaks. It is harder than a steel knife and will scratch glass easily.
Field identification & locations
Identify by its hardness (cannot be scratched by steel) and its granular, sugary texture on fresh breaks. This rounded pebble shape indicates long-distance transport by water.
More like this
