Sandstone (lithic wacke)

Physical Properties

Hardness: 6-7 (Mohs); Color: Tan, brownish-grey; Luster: Dull/Earthy; Crystal structure: Granular/Clastic; Cleavage: None; Specific Gravity: 2.2-2.8

Formation & Geological History

Formed through the accumulation and cementation of sand-sized mineral grains or rock fragments. This specimen appears to be a clastic sedimentary rock formed in a terrestrial or shallow marine environment during various geological ages.

Uses & Applications

Commonly used in construction, as a building stone, in paving, and as an industrial abrasive. Low value for jewelry but significant in architectural history.

Geological Facts

Sandstone accounts for about 10-20% of the Earth's sedimentary rocks. Many sandstone formations are excellent reservoirs for water, oil, and natural gas due to their porosity.

Field Identification & Locations

Identify in the field by its 'gritty' feel (like sandpaper) and visible grains. Often found in layered outcrops or riverbeds. It will not fizz with acid unless it has a calcitic cement.

Identified on: 4/14/2026

Mode: Standard