Sandstone (Quartzose)

Physical Properties

Hardness: 6-7 (on Mohs scale if quartz-rich); Color: Tan, beige, or yellowish brown; Luster: Dull/Earthy; Crystal structure: Clastic (grainy texture); Cleavage: None; Specific gravity: 2.2-2.8

Formation & Geological History

Formed through the accumulation, compaction, and cementation of sand-sized mineral grains or rock fragments. Typically deposited in river beds, beaches, or deserts over millions of years.

Uses & Applications

Widely used as an architectural stone, in paving, as a source of silica for glass making, and for grinding tools. It is also a significant reservoir rock for oil, water, and gas.

Geological Facts

Sandstone makes up about 20-25% of all sedimentary rocks on Earth. The famous red rock formations in Sedona, Arizona and Petra, Jordan are composed primarily of sandstone containing iron oxide.

Field Identification & Locations

Identify in the field by its distinctive 'sandpaper' feel. It is commonly found in sedimentary basins and cliff faces. Collectors look for unique banding or fossil inclusions.

Identified on: 4/20/2026

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