sedimentary

Sandstone (likely Siltstone variety)

Arenite / Siltstone (primary mineral SiO2)

AI-generated identification · may be incorrect

Hardness: 6-7 on Mohs scale; Color: Tan, brown, and grey with reddish iron-oxide staining; Luster: Dull/Earthy; Crystal Structure: Granular/Clastic; Cleavage: None (conchoidal fracture on quartz grains); Specific Gravity: 2.2-2.8

Hardness: 6-7 on Mohs scale
Color: Tan, brown, and grey with reddish iron-oxide staining
Luster: Dull/Earthy

Identified March 25, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation and cementation of mineral particles (sand/silt size) over millions of years. This specimen shows distinct bedding planes (lamination) typical of deposition in low-energy environments like river deltas or lake beds.

Uses & applications

Used in the construction industry as building stone, road base, and concrete aggregate. Fine-grained variants are often used for decorative flagstone or landscape architecture.

Geological facts

Sandstone is one of the most common sedimentary rocks on Earth. The visible layers in this specimen are known as 'laminae' and represent different pulses of sediment deposition, essentially serving as a geological clock.

Field identification & locations

Identify in the field by its gritty texture (feels like sandpaper) and visible layering. It is common worldwide, particularly in the Grand Canyon and the American Southwest. Collectors look for 'landscape' patterns or preserved fossils within the layers.