sedimentary

Red sandstone

Quartz arenite or ferruginous sandstone, composed mainly of quartz (SiO₂) with iron-oxide cement

AI-generated identification · may be incorrect

Typically fine- to medium-grained, reddish-orange, earthy to slightly gritty, with dull to silky luster; hardness about 6–7 for individual quartz grains, no cleavage, and moderate density around 2.2–2.7 g/cm³. The visible specimen appears weathered and possibly cut or broken from a larger slab.

Identified August 23, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed when sand accumulated, was compacted, and cemented by silica or iron oxides, commonly in rivers, deserts, or floodplains. Its exact geological age cannot be determined from the image; red coloration reflects oxidation of iron-bearing minerals.

Uses & applications

Used as building stone, paving, wall material, aggregate, and landscaping stone; attractive varieties are used ornamentally. Common pieces generally have modest collector value.

Geological facts

Iron oxides—especially hematite and limonite—produce the strong red color. Sandstone often preserves sedimentary layers, ripple marks, cross-bedding, and fossils.

Field identification & locations

Identify it by visible sand grains, gritty texture, red iron staining, and sedimentary layering or bedding; it commonly occurs in red-bed formations worldwide, including the American Southwest, England, India, and Australia. The surrounding gravel and grass do not establish its source.