Sandstone (Quartzite-rich)

Physical Properties

Hardness: 6-7 Mohs; Color: Tan, beige, or yellowish-brown; Luster: Dull to earthy; Crystal structure: Granular/clastic; Cleavage: None; Specific Gravity: 2.2–2.8

Formation & Geological History

Formed through the accumulation and cementation of mineral particles or rock fragments (clasts) the size of sand. This specific specimen appears to be a river-worn cobble, smoothed by water transport over long distances.

Uses & Applications

Commonly used as a building material, in the manufacture of glass (if high purity quartz), and as an abrasive. Smooth river stones are popular in landscaping and home decor.

Geological Facts

Sandstone is one of the most common types of sedimentary rock and is found in sedimentary basins throughout the world. It provides important records of geological time and environment of deposition.

Field Identification & Locations

Identify by its gritty, sand-like texture and its ability to scratch glass if it is quartz-rich. This specimen is well-rounded, indicating it was likely found in a riverbed or coastal environment.

Identified on: 4/20/2026

Mode: Standard