Sandstone (with Iron Staining)

Physical Properties

Hardness: 6-7 (Mohs); Color: Tan, yellow, or reddish-brown due to iron oxidation; Luster: Dull/Earthy; Structure: Granular/Clastic; Cleavage: None; Specific Gravity: 2.2-2.8

Formation & Geological History

Formed through the accumulation, compaction, and cementation of sand-sized mineral grains or rock fragments. Often formed in desert, river, or coastal environments over millions of years.

Uses & Applications

Commonly used as a building stone (brownstone), in paving, as a source of silica for glassmaking, and in decorative landscaping.

Geological Facts

Sandstone makes up about 20-25% of all sedimentary rocks on Earth. The 'red rocks' of the American Southwest, like those in the Grand Canyon, are famous examples of massive sandstone formations.

Field Identification & Locations

Identify in the field by its sand-like texture (gritty to the touch like sandpaper) and visible layering or bedding planes. Commonly found in riverbeds and arid regions.

Identified on: 4/13/2026

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