sedimentary

Ferruginous Sandstone (Gozzan-like)

Ferruginous Sandstone (SiO2 with FeO(OH) inclusions)

Hardness: 6-7 (Mohs scale), Color: Rusty brown, reddish-orange to dark chocolate. Luster: Dull or earthy. Structure: Clastic with visible sand-sized grains. Cleavage: None (conchoidal fracture). Specific gravity: 2.5–3.0.

Color: Rusty brown, reddish-orange to dark chocolate
Luster: Dull or earthy

Identified March 19, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the cementation of sand grains by iron-oxide minerals (hematite or limonite). Often occurs in oxidizing environments where iron-rich groundwater interacts with sedimentary layers. Ages range from Paleozoic to Cenozoic.

Uses & applications

Used primarily in construction as a building stone or road aggregate. Some specimens are used in landscape architecture due to their rich, earthy colors. In industry, it can serve as a low-grade iron ore.

Geological facts

Rocks of this type were used by early humans to create earth pigments (ochre). In some regions, these stones are referred to as 'ironstones' and were crucial for early iron-making processes during the Industrial Revolution.

Field identification & locations

Identify in the field by its distinct rust color and gritty, sandpaper-like feel. It will not react with HCl (unlike limestone). Commonly found in dry riverbeds, canyons, and sedimentary basins. Search for areas with visible oxidation.

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