metamorphic
Pebble (likely Quartzite or Sandstone)
Quartzite (SiO2)
Hardness: 7 (Mohs scale); Color: light grey with white speckling; Luster: dull to vitreous when wet; Texture: granular and smooth from water erosion.
- Hardness
- 7 (Mohs scale)
- Color
- light grey with white speckling
- Luster
- dull to vitreous when wet
Identified More metamorphic →
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Physical properties
Hardness: 7 (Mohs scale); Color: light grey with white speckling; Luster: dull to vitreous when wet; Texture: granular and smooth from water erosion.
Formation & geological history
Formed from the metamorphism of quartz sandstone under heat and pressure. This specific specimen has been further shaped by fluvial or coastal water erosion into a rounded pebble.
Uses & applications
Commonly used in landscaping, construction aggregate, and as decorative river stones or pocket stones.
Geological facts
Quartzite is so tough and abrasion-resistant that it can survive long-distance transport in rivers where other rocks would be ground into sand.
Field identification & locations
Identified by its hardness (scratches glass) and granular, 'sugary' appearance under a lens. Found globally in riverbeds and on beaches.
