sedimentary

River Pebble (likely Quartzite or Chert)

Sedimentary Clast (Silicon Dioxide dominant)

AI-generated identification · may be incorrect

Hardness: 6.5-7 on Mohs scale; Color: Tan to light brown with a white quartz vein; Luster: Matte to dull; Crystal structure: Cryptocrystalline; Shape: Rounded/water-worn clast.

Hardness: 6
Color: Tan to light brown with a white quartz vein
Luster: Matte to dull

Identified July 19, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Tan to light brown with a white quartz vein; Luster: Matte to dull; Crystal structure: Cryptocrystalline; Shape: Rounded/water-worn clast.

Formation & geological history

Formed through the erosion of larger rock formations, transported via water (rivers or streams) which rounded the specimen over time. The white line is a secondary quartz vein that filled a fracture in the host rock.

Uses & applications

Primarily used in landscaping, road base, or construction aggregate; sometimes collected as pocket stones or for tumble polishing.

Geological facts

The distinct white line is a vein formed when hydrothermal fluids rich in silica flows through cracks in the rock and crystallize. This specific specimen is known as a 'Wishing Stone' in some folk traditions due to the single continuous ring.

Field identification & locations

Identified by its smooth, water-worn texture and the presence of a distinct mineral vein. Common in riverbeds, glacial deposits, and beaches globally.