sedimentary

Weathered limestone (probable fossiliferous limestone)

Calcite-rich carbonate rock; predominantly calcium carbonate, CaCO₃

AI-generated identification · may be incorrect

Pale gray-beige, dull to earthy luster, fine-grained and irregularly fractured; calcite hardness is about Mohs 3, with good cleavage in individual crystals. The mottled or banded marks may be weathering, bedding, or faint fossil fragments.

Identified September 12, 2026More sedimentary →

Explore Weathered limestone (probable fossiliferous limestone) in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Forms from accumulated carbonate mud, shells, or chemical precipitation in marine settings, commonly during the Paleozoic–Mesozoic; the specimen’s exact age cannot be determined from the image.

Uses & applications

Used for crushed aggregate, cement, lime, building stone, and ornamental slabs; ordinary hand specimens have little commercial value.

Geological facts

Limestone commonly reacts vigorously with dilute hydrochloric acid or household vinegar, producing bubbles, though weathered surfaces may react weakly.

Field identification & locations

Likely limestone if it is relatively soft and fizzes with acid; a knife may scratch it, distinguishing it from harder quartz-rich rocks. Common worldwide, especially in former shallow-marine regions.