sedimentary

Sandstone (likely Graywacke or Siltstone variety)

Clastic Sedimentary Rock (SiO2 with assorted mineral fragments)

AI-generated identification · may be incorrect

Hardness: 6-7 Mohs; Color: Gray, tan, or brownish; Luster: Dull/Earthy; Crystal structure: Clastic (grain-based); Cleavage: None (conchoidal or irregular fracture); Specific gravity: 2.3-2.6

Hardness: 6-7 Mohs
Color: Gray, tan, or brownish
Luster: Dull/Earthy

Identified July 1, 2026More sedimentary →

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Physical properties

Hardness: 6-7 Mohs; Color: Gray, tan, or brownish; Luster: Dull/Earthy; Crystal structure: Clastic (grain-based); Cleavage: None (conchoidal or irregular fracture); Specific gravity: 2.3-2.6

Formation & geological history

Formed through the accumulation and cementation of mineral grains or rock fragments (clasts) usually in marine, river, or desert environments. Often dates from any geological era depending on local strata.

Uses & applications

Used primarily in construction as a building material, aggregate for concrete, and as decorative stone in landscaping. Some fine-grained varieties are used for sharpening tools (whetstones).

Geological facts

Sandstone makes up about 20-25% of all sedimentary rocks on Earth. It is a major reservoir for groundwater, oil, and natural gas due to its porosity and permeability.

Field identification & locations

Identify in the field by its gritty texture (feels like sandpaper) and often visible layering (bedding). It will not fizz with weak acid unless it has a calcitic cement. Found globally in canyon walls and riverbeds.