sedimentary
Sandstone (River Pebble)
Clastic Sedimentary Rock (primarily Quartz)
Hardness: 6-7 (Mohs); Color: Tan, brown, or grey with iron oxide staining; Luster: Dull/Earthy; Texture: Granular/Gritty; Cleavage: None.
- Hardness
- 6-7 (Mohs)
- Color
- Tan, brown, or grey with iron oxide staining
- Luster
- Dull/Earthy
Identified More sedimentary →
Explore Sandstone (River Pebble) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 (Mohs); Color: Tan, brown, or grey with iron oxide staining; Luster: Dull/Earthy; Texture: Granular/Gritty; Cleavage: None.
Formation & geological history
Formed by the accumulation and lithification of sand-sized mineral grains, typically quartz and feldspar, through compaction and cementation. This specific specimen has been water-worn into a smooth pebble shape.
Uses & applications
Used extensively in construction (as aggregate), landscaping, building stone, and occasionally for simple carvings or as a source for quartz in industry.
Geological facts
Sandstone represents about 20% of all sedimentary rocks on Earth. The reddish-brown staining on this specimen is likely due to the oxidation of iron-bearing minerals (limonite or hematite).
Field identification & locations
Identify in the field by its gritty texture (feels like sandpaper) and visible layering (bedding). Found in riverbeds, beaches, and desert environments worldwide.
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
Brown Sandstone (River Rock)
Arenite
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