sedimentary

Fossiliferous Limestone

Biogenic Limestone (CaCO3)

AI-generated identification · may be incorrect

Hardness: 3-4 Mohs; Color: reddish-brown with white inclusions; Luster: earthy to dull; Structure: biogenic/clastic with visible skeletal remains; Gravity: 2.5-2.7

Hardness: 3-4 Mohs
Color: reddish-brown with white inclusions
Luster: earthy to dull

Identified June 19, 2026More sedimentary →

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Physical properties

Hardness: 3-4 Mohs; Color: reddish-brown with white inclusions; Luster: earthy to dull; Structure: biogenic/clastic with visible skeletal remains; Gravity: 2.5-2.7

Formation & geological history

Formed in shallow marine environments from the accumulation of organic debris such as coral, shell, and algal fragments over millions of years, later lithified through cementation.

Uses & applications

Used extensively in the construction industry as building stone, in the production of cement, as lime for soil treatment, and occasionally as decorative lapidary material.

Geological facts

This specimen appears to contain various bioclasts, which are fragments of ancient marine life. Limestone covers about 10% of the total surface area of all sedimentary rocks on Earth.

Field identification & locations

Identified by visible shell/fossil fragments and its reaction (fizzing) to dilute hydrochloric acid. It is commonly found in areas that were once prehistoric seabeds.