sedimentary

Sandstone (Ferruginous)

Arenite with iron oxide cement (Fe2O3)

AI-generated identification · may be incorrect

Hardness: 6-7 (approx); Color: Tan/brown with reddish-orange iron stains; Luster: Dull/earthy; Crystal structure: Clastic (sand grains); Specific Gravity: 2.2-2.8

Hardness: 6-7 (approx)
Color: Tan/brown with reddish-orange iron stains
Luster: Dull/earthy

Identified June 25, 2026More sedimentary →

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Physical properties

Hardness: 6-7 (approx); Color: Tan/brown with reddish-orange iron stains; Luster: Dull/earthy; Crystal structure: Clastic (sand grains); Specific Gravity: 2.2-2.8

Formation & geological history

Formed through the accumulation and cementation of sand-sized mineral grains or rock fragments, likely in a riverbed or coastal environment. The reddish areas suggest oxidation of iron-bearing minerals during or after deposition.

Uses & applications

Common sandstone is used in construction as building stone, pavers, or crushed aggregate. Iron-rich varieties are primarily of interest to collectors or for decorative landscaping.

Geological facts

Sandstone accounts for about 20-25 percent of all sedimentary rocks in the geologic record. The red coloration is often called 'desert varnish' when found on surface exposures.

Field identification & locations

Identify in the field by its gritty texture (feels like sandpaper) and visible layering or staining. Commonly found in sedimentary basins and eroded riverbeds.