metamorphic
Yellow Quartzite (River Pebble)
Crystalline Quartz (SiO2)
Hardness: 7 on Mohs scale (scratches glass). Color: Yellow-tan to cream. Luster: Vitreous to waxy. Crystal Structure: Hexagonal (though usually microcrystalline in this form). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.
- Hardness
- 7 on Mohs scale (scratches glass)
- Color
- Yellow-tan to cream
- 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 (scratches glass). Color: Yellow-tan to cream. Luster: Vitreous to waxy. Crystal Structure: Hexagonal (though usually microcrystalline in this form). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.
Formation & geological history
Formed from the metamorphism of quartz sandstone under intense heat and pressure, followed by mechanical weathering in a river or beach environment which rounded the edges into a smooth pebble.
Uses & applications
Commonly used in landscaping, as aggregate in construction, or as decorative 'pocket stones' for collectors. High-quality pieces are used in stone tumbling and lapidary work.
Geological facts
Quartzite is one of the most durable rocks on Earth's surface. This specific specimen’s yellow hue usually comes from trace amounts of iron oxide (limonite) staining the grains during the metamorphic or weathering process.
Field identification & locations
Identify in the field by its inability to be scratched by a steel knife and its grainy, sugary texture when viewed under a lens compared to smooth chalcedony. Found globally in riverbeds, glacial tills, and beaches.
More like this
