sedimentary
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (SiO2 + Fe2O3)
Hardness: 6-7 (individual grains), 4-5 (matrix); Color: Tanish-brown to reddish-brown; Luster: Dull/Earthy; Crystal structure: Granular/Clastic; Cleavage: None; Specific Gravity: 2.2-2.8
- Hardness
- 6-7 (individual grains), 4-5 (matrix)
- Color
- Tanish-brown to reddish-brown
- Luster
- Dull/Earthy
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 (individual grains), 4-5 (matrix); Color: Tanish-brown to reddish-brown; Luster: Dull/Earthy; Crystal structure: Granular/Clastic; Cleavage: None; Specific Gravity: 2.2-2.8
Formation & geological history
Formed through the accumulation and litification of sand-sized mineral grains or rock fragments, typically in desert, river, or coastal environments. Reddish hues indicate oxidation of iron minerals during burial.
Uses & applications
Commonly used as a building material, for paving stones, grindstones, and as a reservoir rock for oil, gas, and groundwater. Ferruginous varieties are rarely used for jewelry but are popular in landscaping.
Geological facts
Sandstone accounts for approximately 20-25% of all sedimentary rock on Earth. Famous landmarks like the Grand Canyon and Petra are primarily composed of various sandstone formations.
Field identification & locations
Identify by a gritty 'sandpaper' feel when rubbed. It often shows layering (bedding). This specific specimen appears to be a weathered, iron-rich terrestrial fragment.
More like this
Other sedimentary specimens
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