Sandstone (Quartz-rich)

Physical Properties

Hardness: 6-7 (Mohs scale); Color: Tan, beige, light brown; Luster: Dull/Earthy; Crystal Structure: Clastic (sand grains); Cleavage: None; Specific Gravity: 2.2-2.8.

Formation & Geological History

Formed by the accumulation and cementation of sand-sized mineral grains, typically quartz or feldspar. This process (lithification) occurs in riverbeds, deserts, or coastal environments over millions of years.

Uses & Applications

Commonly used in construction as a building material, grit for grinding tools, and as a source for glass manufacturing (if high purity quartz).

Geological Facts

Sandstone is excellent for filtering groundwater because of its permeability. It often preserves fossils and ripple marks from ancient environments.

Field Identification & Locations

Identify in the field by its 'sandpaper' texture. Common in arid regions or uplifted coastal areas. It will feel gritty to the touch and won't react to acid unless it has a calcitic cement.

Identified on: 4/18/2026

Mode: Standard