sedimentary

Likely weathered sandstone or iron-stained sedimentary fragment

Quartz-rich sandstone; exact identification requires testing

AI-generated identification · may be incorrect

Tan-brown, dull to slightly earthy luster, fine-to-medium granular texture, and irregular fracture. Likely hardness about 6–7 if quartz-rich; no obvious cleavage. The apparent vertical line may be a fracture or bedding feature rather than crystal cleavage.

Identified August 11, 2026More sedimentary →

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Physical properties

Formation & geological history

Probably cemented sand deposited in an ancient river, floodplain, shoreline, or basin, then lithified; its geological age cannot be determined from the photograph. The rusty coloration may reflect iron-oxide staining or weathering.

Uses & applications

Common sandstone is used as building stone, paving, aggregate, and occasionally decorative material; this small fragment has little commercial value.

Geological facts

The image does not show diagnostic crystal faces, fossils, or layering clearly enough for a confident species-level identification. It could also be a weathered quartzite or other tan rock.

Field identification & locations

The Petén region near 17.2°N, 89.1°W is dominated largely by carbonate rocks, so a local limestone/dolostone fragment is also plausible, though this specimen looks more granular and siliciclastic. Check with a 10% hydrochloric-acid solution: vigorous fizz suggests limestone; no fizz supports sandstone/quartzite. A steel file should scratch softer sandstone but not quartzite.