Sandstone (likely Ferruginous)

Physical Properties

Hardness: 6-7 (Mohs); Color: Tan, yellow-brown, or rusty orange; Luster: Dull/Earthy; Crystal structure: Clastic (granular); Cleavage: None; Specific Gravity: 2.2–2.8

Formation & Geological History

Formed through the accumulation, compaction, and cementation of sand-sized mineral particles or rock fragments. The brownish coloration suggests iron-oxide (hematite or limonite) acting as a cementing agent.

Uses & Applications

Used primarily as a building material, in decorative masonry, as an abrasive, and sometimes as a reservoir for oil and groundwater.

Geological Facts

Sandstone contains many minerals, but the most common are quartz and feldspar because they are the most resistant to weathering at Earth's surface.

Field Identification & Locations

Identify by its gritty, sandpaper-like texture and visible grains. It is extremely common in desert environments and ancient riverbeds throughout the world.

Identified on: 4/17/2026

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