Sandstone (Grooved/Weathered)

Physical Properties

Hardness: 6-7 (Mohs scale); Color: Tan, beige, or greyish-brown; Luster: Dull/Earthy; Crystal structure: Clastic (granular texture); 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 over millions of years. This specific specimen shows signs of mechanical weathering and aqueous erosion, likely from a fluvial (river) environment.

Uses & Applications

Used widely in construction as a building stone or road base; if naturally shaped, often collected as a 'pocket stone' or decorative garden rock. Some grooved sandstones are historical artifacts (abraders), though this appears natural.

Geological Facts

Sandstone accounts for about 20% of all sedimentary rocks on Earth. Its porosity makes it a valuable reservoir for water, oil, and natural gas. Some grooved specimens were used by indigenous peoples as tools for sharpening bone or wood.

Field Identification & Locations

Identify in the field by its gritty, sandpaper-like feel and visible grains. Common in arid environments, riverbeds, and coastal cliffs. Check if grains can be rubbed off to confirm sedimentary nature.

Identified on: 4/19/2026

Mode: Standard