sedimentary

Chalky limestone

Micritic calcite limestone; predominantly CaCO₃

AI-generated identification · may be incorrect

White to cream, dull and porous, with a fine earthy texture and irregular fracture. Calcite hardness is Mohs 3; it should readily scratch with a steel nail and strongly fizz with dilute hydrochloric acid or vinegar, though vinegar may react slowly. No visible crystal faces or cleavage are evident.

Identified August 10, 2026More sedimentary →

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Physical properties

Formation & geological history

Likely soft carbonate sediment formed from microscopic marine shells or lime mud, later compacted and weakly cemented. Its exact age cannot be determined visually; carbonate rocks are widespread in the Budapest-region hills and nearby Transdanubian formations.

Uses & applications

Used as cement and lime feedstock, aggregate, soil conditioner, and building stone; this loose specimen has little practical or jewelry value.

Geological facts

The powdery appearance and pale color are characteristic of chalky or weathered limestone rather than marble. The smaller piece appears to be a separate fragment of the same material.

Field identification & locations

The regional setting near 47.6°N, 19.3°E makes limestone especially plausible. Confirm by acid fizz, a white streak, and low hardness; avoid acid testing on valuable specimens. It could also be weathered marl or calcite-rich sediment, which requires laboratory testing to distinguish.