sedimentary

Sandstone

Arenite (primarily Quartz Arenite)

Hardness: 6-7 (Mohs scale) if quartz-rich; Color: Tan, brown, or reddish due to iron oxide; Luster: Dull or earthy; Crystal structure: Clastic (sand grains); Specific gravity: 2.2-2.8

Hardness: 6-7 (Mohs scale) if quartz-rich
Color: Tan, brown, or reddish due to iron oxide
Luster: Dull or earthy

Identified May 23, 2026More sedimentary →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 6-7 (Mohs scale) if quartz-rich; Color: Tan, brown, or reddish due to iron oxide; Luster: Dull or earthy; Crystal structure: Clastic (sand grains); Specific gravity: 2.2-2.8

Formation & geological history

Formed through the accumulation and cementation of mineral particles or rock fragments of sand size (0.06 to 2 mm). Most commonly forms in riverbeds, deltas, or desert environments over millions of years.

Uses & applications

Widely used in construction for flagstone, floor tiles, and masonry. Historically used for grinding tools and statues due to its workability and durability.

Geological facts

Sandstone formations act as essential aquifers, holding large amounts of groundwater or petroleum in the pore spaces between the sand grains. Significant portion of the Earth's crust is composed of sandstone.

Field identification & locations

Identify in the field by its gritty texture (feels like sandpaper) and visible layers or bedding. Commonly found in canyons, river valleys, and coastal bluffs. Collectors look for unique concretion patterns or fossils within the layers.