sedimentary
Ferruginous Sandstone
Arenite with Hematite/Limonite cement
Hardness: 6-7 (approx); Color: Rust-brown, orange-red, tan; Luster: Dull/Earthy; Crystal structure: Granular/Clastic; Cleavage: None; Specific Gravity: 2.3-2.8
- Hardness
- 6-7 (approx)
- Color
- Rust-brown, orange-red, tan
- Luster
- Dull/Earthy
Identified More sedimentary →
Explore Ferruginous Sandstone in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 (approx); Color: Rust-brown, orange-red, tan; Luster: Dull/Earthy; Crystal structure: Granular/Clastic; Cleavage: None; Specific Gravity: 2.3-2.8
Formation & geological history
Formed through the accumulation of sand-sized grains, typically quartz, which are later cemented by iron oxides (like hematite or goethite) deposited by groundwater. Common in river beds and desert environments.
Uses & applications
Used primarily as building stone, decorative landscaping rock, and sometimes as a minor source of iron if the concentration is extremely high.
Geological facts
The red colors of the Grand Canyon and the Australian Outback are largely due to iron-stained sandstone like this specimen. The presence of iron indicates an oxidizing environment during or after deposition.
Field identification & locations
Identify by its gritty, sandpaper-like texture and characteristic rust-red streak. Look for it in sedimentary basins and areas with red-bed formations. Collectors look for unique weathering patterns or fossils within the matrix.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Cone-in-cone structure (Limestone)
Cone-in-cone structure (Secondary Sedimentary Structure)
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Sandstone Grain
Clastic Sedimentary Rock Grain (SiO2 dominated)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary