Rock Identifier
Weathered limestone (Calcitic limestone, primarily CaCO₃ (often recrystallized toward marble)) — sedimentary
sedimentary

Weathered limestone

Calcitic limestone, primarily CaCO₃ (often recrystallized toward marble)

AI-generated identification · may be incorrect

Typically Mohs 3; pale cream to gray-brown, earthy to faintly crystalline luster, massive texture, and irregular fractures with possible fossil or solution features. Calcite-rich surfaces fizz vigorously with dilute hydrochloric acid; the image may show weathering and veining.

Identified More sedimentary
Explore Weathered limestone in the encyclopedia →

Identify your own rocks.

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

Physical properties

Typically Mohs 3; pale cream to gray-brown, earthy to faintly crystalline luster, massive texture, and irregular fractures with possible fossil or solution features. Calcite-rich surfaces fizz vigorously with dilute hydrochloric acid; the image may show weathering and veining.

Formation & geological history

Forms from accumulated marine carbonate mud, shells, and skeletal debris, commonly during Paleozoic–Mesozoic seas; later burial, compaction, cementation, and weathering produced this rounded specimen. Exact age and locality cannot be determined from the photograph.

Uses & applications

Used for aggregate, cement and lime, building stone, soil neutralization, and ornamental slabs; attractive fossiliferous or veined pieces are collected.

Geological facts

Limestone is one of Earth’s most widespread sedimentary rocks and commonly records ancient shallow-sea environments. Groundwater can dissolve it, creating caves, cavities, and irregular surface relief.

Field identification & locations

Look for calcite fizz, relatively low hardness, pale color, and sedimentary layering or fossils; distinguish marble by its more uniformly crystalline mosaic and weaker visible bedding. Common worldwide, especially in former marine basins.