metamorphic
Yellow Quartzite
Quartzite (primarily SiO2)
Hardness: 7 on Mohs scale. Color: Yellow to tan due to iron oxide staining. Luster: Vitreous to dull. Crystal structure: Trigonal (microcrystalline). Cleavage: None (conchoidal fracture). Specific Gravity: 2.6 - 2.7.
- Hardness
- 7 on Mohs scale
- Color
- Yellow to tan due to iron oxide staining
- 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 on Mohs scale. Color: Yellow to tan due to iron oxide staining. Luster: Vitreous to dull. Crystal structure: Trigonal (microcrystalline). 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. The original sand grains recrystallize into a dense, interlocking mosaic of quartz crystals. Geological age can range from Precambrian to Cenozoic.
Uses & applications
Used as crushed stone for road construction, railroad ballast, and decorative landscaping. High-purity quartzite is used to produce silica sand for glassmaking and industrial abrasives.
Geological facts
Quartzite is so tough that it often outlasts the surrounding rocks during erosion, frequently forming the tops of ridges and mountains. It is more resistant to chemical weathering than most other rocks.
Field identification & locations
Identify in the field by its extreme hardness (it will scratch glass) and its sugary texture on fresh breaks. Look for it in metamorphic belts or as rounded river cobbles in regions with glaciated terrain.
More like this
