sedimentary
Ferruginous Sandstone
Sandstone with Iron Oxide (Limonite/Goethite)
Hardness: 6-7 (Mohs scale), Color: Rusty brown, orange, and tan, Luster: Dull/Earthy, Crystal Structure: Granular/Clastic, Specific Gravity: 2.0-2.6
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 (Mohs scale), Color: Rusty brown, orange, and tan, Luster: Dull/Earthy, Crystal Structure: Granular/Clastic, Specific Gravity: 2.0-2.6
Formation & geological history
Formed through the accumulation and cementation of sand-sized mineral grains or rock fragments, deeply colored by iron oxide minerals (rust) deposited by groundwater. Typical of various geological ages from Paleozoic to Cenozoic.
Uses & applications
Commonly used as building stone, flagstone for landscaping, and as a source of aggregate in construction.
Geological facts
The intense orange and brown color is caused by the oxidation of iron minerals within the rock, similar to how metal rusts. These rocks are often used to study ancient groundwater flow patterns.
Field identification & locations
Identify in the field by its gritty texture (feels like sandpaper) and its distinct reddish-brown staining which often forms a 'rind' on the exterior. Found globally in sedimentary basins.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone Grain
Clastic Sedimentary Rock Grain (SiO2 dominated)
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Sandstone
Arenite
sedimentary