metamorphic
Quartzite with Quartz Veining
Quartzite (consisting primarily of SiO2)
Hardness: 7 on Mohs scale; Color: Grey, white, with minor iron staining (orange spot); Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal system (microcrystalline); Specific gravity: approx. 2.65.
- Hardness
- 7 on Mohs scale
- Color
- Grey, white, with minor iron staining (orange spot)
- 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: Grey, white, with minor iron staining (orange spot); Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal system (microcrystalline); Specific gravity: approx. 2.65.
Formation & geological history
Formed from the regional metamorphism of quartz-rich sandstone. Under intense heat and pressure, the sand grains recrystallize and fuse together, often creating veins where hydrothermal fluids deposited additional silica.
Uses & applications
Used primarily in construction as crushed stone or decorative landscaping. High-purity quartzite is used to produce ferrosilicon, industrial silica sand, and silicon metal.
Geological facts
Quartzite is so tough that it often breaks through the constituent sand grains rather than around them, which distinguishes it from sandstone. This specific piece shows significant water-wear, suggesting a fluvial or glacial history.
Field identification & locations
Identify in the field by its inability to be scratched by a steel knife and its grainy but crystalline 'sugary' texture. Commonly found in folded mountain belts globally.
More like this
