Sandstone (likely Arkosic or Lithic Sandstone)

Physical Properties

Hardness: 6-7 (Mohs scale), Color: Tan to light brown with irony staining, Luster: Dull/Earthy, Crystal Structure: Clastic/Granular, Cleavage: None, Specific Gravity: 2.2-2.8

Formation & Geological History

Formed through the accumulation and cementation of sand-sized mineral grains or rock fragments. This process occurs in environments such as river beds, deserts, or marine deltas over millions of years through lithification.

Uses & Applications

Commonly used as a building material, in decorative landscaping, for glass manufacturing (if high silica content), and as a reservoir rock for oil and natural gas.

Geological Facts

Sandstone makes up about 20-25% of all sedimentary rocks on Earth. The famous red rock formations in Sedona, Arizona and the Grand Canyon are composed primarily of varied sandstone layers.

Field Identification & Locations

Identify in the field by its gritty 'sandpaper' feel and visible grain layers. Look for it in outcrops where erosion has exposed horizontal bedding. It is a fundamental rock for learning about sedimentary processes.

Identified on: 4/23/2026

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