sedimentary

Red Sandstone

Sedimentary Clastic Rock (Quartz Arenite / Arkose)

Hardness: 6-7 on Mohs scale (due to quartz grains); Color: Red, reddish-brown, or rust colored from iron oxide cement; Luster: Dull or earthy; Structure: Clastic, composed of cemented mineral particles or rock fragments ranging from 0.0625 mm to 2 mm in size.

Hardness: 6-7 on Mohs scale (due to quartz grains)
Color: Red, reddish-brown, or rust colored from iron oxide cement
Luster: Dull or earthy

Identified August 4, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the accumulation, compaction, and cementation of mineral particles or rock fragments, typically in desert dune environments, river channels, or shallow marine settings, often dating from the Paleozoic to Mesozoic eras.

Uses & applications

Commonly used in construction, architectural building stone, paving, and landscaping.

Geological facts

The distinctive red color is caused by iron oxide (hematite) coating the sand grains, often indicating deposition in an arid or semi-arid oxidizing terrestrial environment.

Field identification & locations

Easily identified by its granular texture, visible sand grains, and reddish coloration. Frequently found in riverbeds, coastal areas, and ancient sedimentary basins worldwide.

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Sandstone or Siltstone

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Generic Pebble / Rock Fragment

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Sedimentary Sandstone

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Banded Siltstone / Mudstone Pebble

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