metamorphic
Yellow Quartzite
Quartzite (SiO2)
Hardness: 7 on Mohs scale; Color: Yellowish-orange due to iron oxide staining; Luster: Vitreous to waxy when water-worn; Structure: Granular, non-foliated crystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.7
- Hardness
- 7 on Mohs scale
- Color
- Yellowish-orange due to iron oxide staining
- Luster
- Vitreous to waxy when water-worn
Identified More metamorphic →
Explore Yellow Quartzite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 on Mohs scale; Color: Yellowish-orange due to iron oxide staining; Luster: Vitreous to waxy when water-worn; Structure: Granular, non-foliated crystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.7
Formation & geological history
Formed through the metamorphism of quartz-rich sandstone. Under intense heat and pressure, quartz grains recrystallize and fuse together. These specimens are often rounded by fluvial or glacial transport.
Uses & applications
Used primarily as decorative stone, in construction aggregates, and for landscaping. High-purity quartzite is used in the manufacture of glass and silicon.
Geological facts
Quartzite is so tough that it often survives intense erosion that wears away surrounding softer rocks. It can be distinguished from sandstone because it breaks through the quartz grains rather than around them.
Field identification & locations
Identify in the field by its extreme hardness (cannot be scratched by a steel knife) and its grainy, sugary texture. This water-molded pebble was likely found in a riverbed or coastal area.
More like this
