Sandstone (Quartzose)

Physical Properties

Hardness: 6-7 (Mohs scale); Color: Tan, brown, reddish; 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. Typically deposited in riverbeds, deserts, or marine environments over millions of years.

Uses & Applications

Used widely as a building material, in the manufacture of glass (if high quartz content), and as a reservoir rock for oil and natural gas.

Geological Facts

Sandstone makes up about 20% of all sedimentary rocks on Earth. The famous red rocks of the Grand Canyon and Zion National Park are composed largely of various sandstone layers.

Field Identification & Locations

Identify by its gritty, sand-paper-like feel. It can be found in sedimentary basins worldwide. For collectors, look for cross-bedding patterns or fossil inclusions.

Identified on: 4/13/2026

Mode: Standard