metamorphic
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Hardness: 7 on Mohs scale; Color: White to yellowish-tan; Luster: Vitreous to waxy; Crystal structure: Hexagonal (trigonal); Grainy texture like sandpaper but smooth to touch.
- Hardness
- 7 on Mohs scale
- Color
- White to yellowish-tan
- 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: White to yellowish-tan; Luster: Vitreous to waxy; Crystal structure: Hexagonal (trigonal); Grainy texture like sandpaper but smooth to touch.
Formation & geological history
Formed through the regional metamorphism of quartz-rich sandstone. High heat and pressure cause the sand grains to recrystallize and fuse together.
Uses & applications
Used as a decorative stone in construction, as aggregate in road building, and in glass manufacturing or as a refractory material due to high heat resistance.
Geological facts
Quartzite is so tough that it often survives intense weathering that erodes other rocks away, frequently topped by hills or ridges known as 'quartzite hogbacks'.
Field identification & locations
Identify by its hardness (it will scratch glass easily) and the way it breaks across grains rather than around them. Found globally in ancient mountain belts.
More like this
