sedimentary

Sandstone (Ferruginous)

Arenite (primarily SiO2 with iron oxide staining/cementing)

AI-generated identification · may be incorrect

Hardness: 6-7 (Mohs scale for quartz grains); Color: Tan, brown, or rusty orange; Luster: Dull or earthy; Crystal structure: Granular/clastic; Cleavage: None (fractures across grains); Specific Gravity: 2.2-2.8

Hardness: 6-7 (Mohs scale for quartz grains)
Color: Tan, brown, or rusty orange
Luster: Dull or earthy

Identified May 17, 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

Formation & geological history

Formed through the accumulation and cementation of sand-sized mineral grains or rock fragments. The brown color indicates the presence of iron oxide (hematite or limonite) as a cementing agent or coating. These specimens are often found in riverbeds, deserts, or marine environments and can range from many millions to hundreds of millions of years old.

Uses & applications

Used widely as a building material, in the manufacture of glass (if high silica), and as a reservoir rock for oil and natural gas. Some varieties are used for decorative landscaping.

Geological facts

Sandstone contains a significant portion of the Earth's groundwater. It is often responsible for iconic landscape features like the canyons in the American Southwest.

Field identification & locations

Identify in the field by its gritty texture (feels like sandpaper) and visible sand grains. It is often found in stratified layers. For collectors, look for unique colors or fossil inclusions.