sedimentary

Red Sandstone

Arenite (Iron-rich)

Hardness 6.5-7 (individual grains); Color: brick red, reddish-brown; Luster: matte to dull; Texture: granular, gritty; Cleavage: none; Structure: clastic.

Color: brick red, reddish-brown
Luster: matte to dull

Identified July 19, 2026More sedimentary →

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Physical properties

Hardness 6.5-7 (individual grains); Color: brick red, reddish-brown; Luster: matte to dull; Texture: granular, gritty; Cleavage: none; Structure: clastic.

Formation & geological history

Formed through the accumulation and cementation of sand-sized mineral particles, primarily quartz. The red color suggests deposition in an oxygen-rich environment (terrestrial) where iron oxide (hematite) coated the grains. Ages range from Precambrian to Holocene.

Uses & applications

Construction material, landscaping, architectural stone, and geological educational specimens.

Geological facts

The red color is caused by the oxidation of iron minerals, essentially rusting within the rock layers. Famous formations include the Grand Canyon and the Australian Outback.

Field identification & locations

Identify by its sandpaper-like feel and the fact that it will rub off slightly red if scratched. Common in arid or formerly arid environments like the American Southwest.