Sandstone (Quartzose Sandstone)

Physical Properties

Hardness: 6-7 Mohs scale; Color: Tan, beige, or gray; Luster: Dull/Earthy; Crystal Structure: Clastic grains visible under magnification; 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 in river beds, deserts, or coastal environments. It can represent various geological ages from Precambrian to recent Cenozoic deposits.

Uses & Applications

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

Geological Facts

Sandstone accounts for roughly 20-25% of all sedimentary rocks on Earth. The famous red rock formations of the American Southwest are composed of layered sandstone.

Field Identification & Locations

Identify in the field by its gritty texture (feels like sandpaper) and visible sand grains. Commonly found in coastal areas, river basins, and areas with exposed sedimentary strata. Collectors look for unique banding or fossils within.

Identified on: 4/14/2026

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