sedimentary

Weathered limestone

Calcite-rich carbonate rock; predominantly CaCO₃

AI-generated identification · may be incorrect

Typically Mohs hardness 3, pale gray to buff, earthy to dull luster, very fine- to coarse-grained texture, and poor or indistinct cleavage as a rock. The specimen appears strongly weathered and may contain minor clay, iron oxides, or fossil material.

Identified September 5, 2026More sedimentary →

Explore Weathered 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

Formed from accumulated marine carbonate mud, shells, or skeletal debris that lithified into limestone, commonly during the Paleozoic–Cenozoic eras. Surface alteration has produced the rough, pitted appearance.

Uses & applications

Used as aggregate, crushed stone, cement and lime feedstock, building stone, and occasionally as a decorative material. Collecting value is generally low unless fossiliferous or unusually textured.

Geological facts

Calcite-rich limestone effervesces vigorously with dilute hydrochloric acid or household vinegar, especially on a freshly broken surface. Weathering can dissolve calcite and leave an irregular, porous exterior.

Field identification & locations

Common worldwide, especially in former shallow marine basins; major occurrences include the United States, Europe, China, and the Caribbean. Confirm identification with an acid test, relatively low hardness, and a white streak.