sedimentary

Sandstone (Ferruginous)

Arenite (SiO2 with Iron Oxide impurities)

AI-generated identification · may be incorrect

Hardness: 6-7 (Mohs scale); Color: Brown, tan, reddish-brown; Luster: Dull, earthy; Crystal structure: Amorphous/Granular grains; Cleavage: None; Specific gravity: 2.2-2.8

Hardness: 6-7 (Mohs scale)
Color: Brown, tan, reddish-brown
Luster: Dull, earthy

Identified April 7, 2026More sedimentary →

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Physical properties

Hardness: 6-7 (Mohs scale); Color: Brown, tan, reddish-brown; Luster: Dull, earthy; Crystal structure: Amorphous/Granular grains; 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 (clasts). The brown color suggests the presence of iron oxide (hematite or limonite). These form in river, desert, or marine environments over millions of years.

Uses & applications

Used primarily in building construction as a paving or wall material; crushed for road base; also used as a reservoir rock for oil and gas.

Geological facts

Sandstone is one of the most common sedimentary rocks on Earth. It often preserves fossils and ripple marks from ancient water bodies, providing clues to Earth's past climate.

Field identification & locations

Identify in the field by its sandy, gritty texture (feels like sandpaper) and visible layering (bedding). Commonly found in canyons, dry riverbeds, and sedimentary basins.