Sandstone (with potentially high Feldspar/Arkose content)

Physical Properties

Hardness (Mohs scale): 6-7; Color: Tan, beige, light brown; Luster: Dull/Earthy; Crystal structure: Granular-clastic; Cleavage: None (fractures across grains); Specific gravity: 2.2-2.8

Formation & Geological History

Formed through the accumulation and cementation of mineral particles or rock fragments (sand) in marine or terrestrial environments. Often associated with ancient riverbeds or desert dunes.

Uses & Applications

Used extensively as a building material, in decorative masonry, as road base, and as a reservoir rock for petroleum and natural gas exploration.

Geological Facts

Sandstone accounts for roughly 20 to 25 percent of all sedimentary rocks on Earth. The famous red rock formations in Sedona, Arizona and Zion National Park are prime examples of this rock type.

Field Identification & Locations

Identify in the field by its gritty texture (feels like sandpaper) and visible layering (bedding planes). It is commonly found in basins or former coastal areas. Use a hand lens to see individual sand grains.

Identified on: 4/19/2026

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