Rock Identifier
Weathered sandstone fragment (Quartz-rich sandstone (compositionally uncertain)) — sedimentary
sedimentary

Weathered sandstone fragment

Quartz-rich sandstone (compositionally uncertain)

AI-generated identification · may be incorrect

Tan, granular upper surface with a dark gray-brown, irregularly weathered exterior; likely Mohs hardness 6–7 for quartz grains, with earthy to dull luster and no visible cleavage. The apparent layering or planar break is typical of sedimentary rock.

Identified More sedimentary
Explore Weathered sandstone fragment in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

Physical properties

Tan, granular upper surface with a dark gray-brown, irregularly weathered exterior; likely Mohs hardness 6–7 for quartz grains, with earthy to dull luster and no visible cleavage. The apparent layering or planar break is typical of sedimentary rock.

Formation & geological history

Likely formed by burial, compaction, and cementation of sand, commonly during the Paleozoic–Mesozoic or younger; the exact age and environment cannot be determined from the photograph. Iron oxides may produce the yellow-tan coloration, while weathering darkens the exposed faces.

Uses & applications

Common sandstone is used as building stone, paving, aggregate, and occasionally decorative material; this small fragment has little commercial value unless it proves unusual or fossiliferous.

Geological facts

Sandstone is identified by visible sand-sized grains, often dominated by quartz, feldspar, and rock fragments bound by silica, calcite, or iron oxides. The specimen may alternatively be a weathered fine-grained volcanic or metamorphic rock, so a hand lens and hardness test would improve identification.

Field identification & locations

Look for gritty texture, discrete grains, sedimentary layering, and a lack of strong foliation; common sources include deserts, river channels, beaches, and sedimentary basins worldwide. Estimated value: $1–$10 as an ordinary fragment, or $10–$50 if locally distinctive or fossil-bearing.