sedimentary
Red Sandstone
Arenite (primarily Quartz with Hematite cement)
Hardness: 6-7 on Mohs scale; Color: Red, reddish-brown, or terracotta due to iron oxide; Luster: Dull/Earthy; Crystal structure: Granular/Clastic; Cleavage: None; Specific gravity: 2.2-2.8
- Hardness
- 6-7 on Mohs scale
- Color
- Red, reddish-brown, or terracotta due to iron oxide
- 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 on Mohs scale; Color: Red, reddish-brown, or terracotta due to iron oxide; Luster: Dull/Earthy; Crystal structure: Granular/Clastic; Cleavage: None; Specific gravity: 2.2-2.8
Formation & geological history
Formed through the accumulation, compaction, and cementation of sand-sized mineral grains (mostly quartz). The red color indicates formation in an oxygen-rich environment, often in arid terrestrial settings like deserts or river floodplains (Old Red Sandstone/New Red Sandstone eras).
Uses & applications
Extensively used in construction as a building stone (brownstones), for paving, decorative landscaping, and architectural facades. Historically used for monuments and carving.
Geological facts
Red sandstone is responsible for the famous 'Red Rocks' of the American Southwest and the historic 'Old Red Sandstone' formations in Great Britain, which were pivotal in the development of the science of geology.
Field identification & locations
Identify by its gritty, sandpaper-like texture and visible sand grains. Found globally in basins and sedimentary outcroppings. Collectors look for unique banding or wave-ripple patterns preserved in the stone.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Sandstone (Quartz-rich)
Arenite (SiO2)
sedimentary
Sandstone (with man-made markings)
Arenite (composed primarily of Quartz, SiO2)
sedimentary