metamorphic
Quartzite Pebble
Metamorphic Quartz (SiO2)
Hardness: 7 on Mohs scale; Color: Cream, tan, or yellow-stained with iron oxide; Luster: Dull to vitreous; Structure: Crystalline but often seen as rounded water-worn cobbles; Cleavage: None (conchoidal fracture).
- Hardness
- 7 on Mohs scale
- Color
- Cream, tan, or yellow-stained with iron oxide
- Luster
- Dull to vitreous
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: Cream, tan, or yellow-stained with iron oxide; Luster: Dull to vitreous; Structure: Crystalline but often seen as rounded water-worn cobbles; Cleavage: None (conchoidal fracture).
Formation & geological history
Formed from quartz-rich sandstone subjected to high pressure and heat (metamorphism), subsequent erosion by river or coastal action rounded this specimen into a pebble.
Uses & applications
Quartzite is used heavily in road construction, as railway ballast, and in the manufacturing of glass and ceramics; smooth pebbles are used for decorative landscaping.
Geological facts
Quartzite is so tough that it often outlasts the surrounding rock layers during erosion, frequently being the material that makes up mountain peaks or river bed cobbles.
Field identification & locations
Identify by its ability to scratch glass and lack of reaction to acid. Commonly found in riverbeds, glacial tills, and ancient beach deposits.
More like this
