Red Sandstone

Physical Properties

Hardness: 6-7 (on Mohs scale if quartz-rich); Color: Red, reddish-brown, or orange due to hematite; Luster: Dull/Earthy; Structure: Clastic, fine to medium-grained; Cleavage: None/Conchoidal fractures.

Formation & Geological History

Formed through the accumulation and cementation of sand-sized mineral particles or rock fragments. The red color suggests deposition in an oxygen-rich terrestrial environment, such as a desert or river flood plain, where iron minerals oxidize (rust).

Uses & Applications

Used widely as a building material, paving stone, and in glass manufacturing or as a source of industrial sand. Also popular among collectors for its aesthetic coloring.

Geological Facts

Many famous geological formations are composed of red sandstone, including the Grand Canyon and the 'Red Rocks' of Colorado. It often contains ripple marks or cross-bedding from ancient winds and waters.

Field Identification & Locations

Identify in the field by its gritty texture (feels like sandpaper) and distinct red staining that won't wash off. It is commonly found in sedimentary basins and arid regions.

Identified on: 4/17/2026

Mode: Standard