sedimentary

Fossiliferous Limestone

Biogenic Limestone (predominantly CaCO3)

AI-generated identification · may be incorrect

Hardness: 3 on Mohs scale; Color: tan, beige, off-white, and brownish-grey; Luster: dull to earthy; Texture: clastic/bioclastic with visible internal fossil cavity or mold; Specific Gravity: ~2.3 - 2.7

Hardness: 3 on Mohs scale
Color: tan, beige, off-white, and brownish-grey
Luster: dull to earthy

Identified October 17, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed in warm, shallow marine environments from the accumulation of calcium carbonate shell fragments, skeletal debris, and precipitated calcite mud over millions of years (commonly Paleozoic to Mesozoic era).

Uses & applications

Commonly used in construction as crushed stone, dimension stone, cement manufacturing, agricultural soil treatment, and collected as natural fossil specimens.

Geological facts

Limestone covers about 10% of total sedimentary rock exposure globally, and fossiliferous varieties provide critical historical records of prehistoric marine ecosystems.

Field identification & locations

Easily identified in the field by vigorous effervescence when exposed to cold dilute hydrochloric acid (acid test), moderate softness (scratched easily by a copper coin or pocketknife), and the presence of embedded fossilized impressions or shell remains.