sedimentary
Red Sandstone / Mudstone Nodules (L Liesegang rings)
Sedimentary Rock (Quartz/Hematite Clay Mix)
Mohs hardness 2-6 depending on cementation, reddish-brown to pinkish-tan coloration due to iron oxides (hematite), earthy to dull luster, fine-grained clastic texture, no prominent cleavage.
Identified More sedimentary →
Explore Red Sandstone / Mudstone Nodules (L Liesegang rings) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Mohs hardness 2-6 depending on cementation, reddish-brown to pinkish-tan coloration due to iron oxides (hematite), earthy to dull luster, fine-grained clastic texture, no prominent cleavage.
Formation & geological history
Formed by the accumulation and compaction of mineral particles or rock fragments, cemented together by silica, calcite, or iron oxide. The reddish coloration indicates deposition in an oxygen-rich continental environment, such as river floodplains or desert dunes.
Uses & applications
Used as decorative garden stone, building stone, dimension stone, or as specimens for educational collections.
Geological facts
Red sedimentary rocks get their distinctive rusty-red color from minute amounts of hematite coating the individual sand or silt grains. The concentric banding often seen in such rocks is caused by Liesegang ring formation via chemical precipitation.
Field identification & locations
Identified in the field by its fine grain, earthy feel, reddish-brown iron staining, and soft-to-medium hardness. Commonly found in sedimentary basins worldwide, including the American Southwest and parts of Europe.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sedimentary Sandstone
Arenite (Sedimentary Rock)
sedimentary
Fossiliferous Concretion
Septarian Concretion containing Brachiopods/Crinoids
fossil
Shale
Shale (clastic sedimentary rock)
sedimentary
Shale
Argillaceous sedimentary rock
sedimentary
Mudstone
Argillite / Siliciclastic sedimentary rock
sedimentary