Sandstone

Physical Properties

Hardness: 6-7 (if quartz-based); Color: tan, yellow, brown, or red; Luster: dull/earthy; Crystal structure: clastic (granular); 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. These deposits typically occur in river beds, beaches, or deserts over millions of years.

Uses & Applications

Extensively used in construction for paving, walling, and decorative veneers. It is also a critical reservoir rock for groundwater, petroleum, and natural gas.

Geological Facts

Sandstone makes up about 20-25% 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, sandpaper-like texture and visible grains. It is commonly found in sedimentary basins and coastal regions. It often shows layering or cross-bedding features.

Identified on: 4/25/2026

Mode: Standard