metamorphic
Quartzite Pebble
Quartzite (SiO2)
Hardness: 7 (Mohs scale); Color: Creamy white to light brown; Luster: Vitreous to dull; Crystal structure: Trigonal (microcrystalline); Cleavage: None, conchoidal fracture; Specific gravity: 2.6 to 2.7
- Hardness
- 7 (Mohs scale)
- Color
- Creamy white to light brown
- 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 (Mohs scale); Color: Creamy white to light brown; Luster: Vitreous to dull; Crystal structure: Trigonal (microcrystalline); Cleavage: None, conchoidal fracture; Specific gravity: 2.6 to 2.7
Formation & geological history
Formed from the metamorphism of quartz sandstone under high heat and pressure. This specific specimen has been further smoothed and rounded through fluvial or glacial erosion processes over thousands of years.
Uses & applications
Commonly used as construction aggregate, ballast for railroads, landscaping material, and when high purity, used to produce silica sand for glassmaking.
Geological facts
Quartzite is so tough that it often outlasts the surrounding softer rocks in a landscape, often forming the caps of ridges and mountains. It is one of the most chemically resistant rocks on Earth.
Field identification & locations
Identify in the field by its hardness (will scratch glass) and its grainy, sugary appearance compared to chert. Found globally in riverbeds, glacial tills, and mountainous metamorphic belts.
More like this
