sedimentary

Fossiliferous Limestone

Calcium Carbonate - CaCO3

AI-generated identification · may be incorrect

Hardness: 3 on Mohs scale; Color: Gray, tan, or white with visible fossil fragments; Luster: Dull to earthy; Structure: Biological sediment/massive; Cleavage: None (fractures irregularly).

Hardness: 3 on Mohs scale
Color: Gray, tan, or white with visible fossil fragments
Luster: Dull to earthy

Identified May 17, 2026More sedimentary →

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Physical properties

Hardness: 3 on Mohs scale; Color: Gray, tan, or white with visible fossil fragments; Luster: Dull to earthy; Structure: Biological sediment/massive; Cleavage: None (fractures irregularly).

Formation & geological history

Formed in warm, shallow marine environments where skeletal fragments of marine organisms (such as coral, mollusks, or crinoids) accumulate and are lithified over millions of years.

Uses & applications

Used in construction as aggregate, in the manufacture of cement, and as a soil conditioner in agriculture. Higher quality pieces are kept by fossil collectors.

Geological facts

Limestone contains about 10% of the total volume of all sedimentary rocks. It is often the primary source of fossils for researchers studying ancient marine life.

Field identification & locations

Identify in the field by looking for visible shell fragments or small pore-like structures (bryozoans/corals). It will react and fizz when exposed to dilute hydrochloric acid.