sedimentary

Sandstone (Ferruginous)

Ferruginous Sandstone (SiO2 with Fe2O3)

AI-generated identification · may be incorrect

Hardness: 6-7 on Mohs scale; Color: Reddish-brown, tan, or ochre; Luster: Dull to earthy; Crystal Structure: Clastic (grains); Cleavage: None; Specific Gravity: 2.2-2.8.

Hardness: 6-7 on Mohs scale
Color: Reddish-brown, tan, or ochre
Luster: Dull to earthy

Identified June 23, 2026More sedimentary →

Explore Sandstone (Ferruginous) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 6-7 on Mohs scale; Color: Reddish-brown, tan, or ochre; Luster: Dull to earthy; Crystal Structure: Clastic (grains); Cleavage: None; Specific Gravity: 2.2-2.8.

Formation & geological history

Formed by the accumulation and cementation of sand-sized mineral grains or rock fragments. The reddish hue indicates iron oxide (hematite or limonite) acting as the cementing agent. Often associated with ancient riverbeds, deserts, or marine environments across various geological ages.

Uses & applications

Historically used as a construction material for buildings and monuments. In modern times, it is used for gravel, paving stones, or as a source of silica for glass manufacturing.

Geological facts

Sandstone represents about 20-25% of all sedimentary rocks on Earth. Ferruginous sandstone is specifically known for its distinct color which comes from the oxidation of iron minerals, similar to the process of rusting.

Field identification & locations

Identified by its gritty sandpaper-like texture and visible sand grains. Found globally in sedimentary basins. Collectors look for unique banding or patterns caused by mineral staining.