Red Sandstone (Hematitic)

Physical Properties

Hardness: 6-7 (if quartz-rich); Color: Dark reddish-brown to maroon; Luster: Dull/Earthy; Crystal structure: Granular/Clastic; Cleavage: None; Specific Gravity: 2.2-2.8

Formation & Geological History

Formed through the accumulation and cementation of mineral particles or rock fragments. The red color suggests deposition in an oxygen-rich environment where iron minerals oxidized (rusted). Often associated with ancient river beds or desert dunes.

Uses & Applications

Used in landscaping, construction as a building stone (brownstone), and as a decorative garden pebble due to its smooth water-worn texture.

Geological Facts

The red color is specifically due to a thin coating of iron oxide (hematite) around the individual sand grains. This specific rounded shape is the result of mechanical weathering in a high-energy water environment like a river or beach.

Field Identification & Locations

Identify in the field by its gritty texture (feels like sandpaper) and its ability to leave a light streak if rubbed on a harder surface. This specimen is well-rounded, indicating significant travel from its source rock.

Identified on: 4/23/2026

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