Sandstone

Physical Properties

Hardness: 6-7 Mohs; Color: Tan, gray, or yellow; Luster: Dull/Earthy; Crystal Structure: Clastic (grains of quartz/feldspar); Cleavage: None; Specific Gravity: 2.2-2.8

Formation & Geological History

Formed through the accumulation of sand-sized mineral particles and organic matter, then lithified by pressure and mineral cement over millions of years in marine or desert environments.

Uses & Applications

Widely used in construction for building stone, road base, and as a raw material for making glass (if high silica). Frequently used for pavers and ornamental architecture.

Geological Facts

Sandstone makes up about 10 to 25 percent of the sedimentary rocks on Earth. It is a major aquifer for ground water and a common reservoir for oil and natural gas.

Field Identification & Locations

Identify by its gritty texture (feels like sandpaper) and visible layering (bedding). Found worldwide in basins and coastal exposures. Collectors look for unique color bands or fossil inclusions.

Identified on: 5/20/2026

Mode: Standard