sedimentary

Sandstone (Ferruginous)

Sandstone (primarily SiO2 with iron oxide cement Fe2O3)

Hardness: 6-7 on Mohs scale; Color: Tan, brown, or reddish due to iron oxidation; Luster: Dull or earthy; Crystal structure: Clastic (granular); Cleavage: None (breaks across grains); Specific Gravity: 2.2-2.8

Hardness: 6-7 on Mohs scale
Color: Tan, brown, or reddish due to iron oxidation
Luster: Dull or earthy

Identified June 21, 2026More sedimentary →

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 (lithification). This specimen shows weathering and iron-staining, suggesting formation in a high-energy depositional environment like a riverbed or desert, followed by exposure to oxygen and moisture.

Uses & applications

Commonly used as a building material, decorative stone, in glass manufacturing (if high silica content), and as an abrasive.

Geological facts

Sandstone can store large amounts of water or oil in its pores, acting as a natural reservoir. It is one of the most common sedimentary rocks in the Earth's crust.

Field identification & locations

Identify by its gritty, sandpaper-thick texture. It often shows visible layers (bedding planes). Found globally in sedimentary basins, canyons, and coastal areas. Collectors should look for unique cross-bedding patterns or fossils.

Other sedimentary specimens

See all

Sandstone or Siltstone

Arenite (if sandstone)

Sedimentary

Chert Breccia

Brecciated Chert (Microcrystalline Silica)

sedimentary

Sandstone

Arenite (primarily SiO2)

sedimentary

Sandstone Grain

Clastic Sedimentary Rock Grain (SiO2 dominated)

sedimentary

Shale or Slaty Mudstone

Argillaceous sedimentary rock

sedimentary

Sandstone

Arenite

sedimentary