sedimentary
Fossiliferous limestone
Bioclastic limestone, chiefly calcite (CaCO₃), with a visible fossil shell or fossil fragment
AI-generated identification · may be incorrectGray-beige, rough, and nonmetallic, with fossil-like structures in a fine-grained carbonate matrix; calcite is Mohs 3 and reacts with dilute acid. The small specimen’s exact mineral makeup and fossil identity cannot be confirmed from the image alone.
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Physical properties
Gray-beige, rough, and nonmetallic, with fossil-like structures in a fine-grained carbonate matrix; calcite is Mohs 3 and reacts with dilute acid. The small specimen’s exact mineral makeup and fossil identity cannot be confirmed from the image alone.
Formation & geological history
Forms as marine carbonate sediment accumulates and is compacted and cemented, preserving shells and other remains. Its age depends on the fossil and locality and cannot be determined from the image.
Uses & applications
Limestone is widely used for cement, aggregate, and building stone; fossil-rich pieces are mainly collected or used decoratively.
Geological facts
Fossiliferous limestone preserves evidence of ancient marine life and environments.
Field identification & locations
Look for recognizable shell, coral, or other fossil shapes embedded in a carbonate matrix; a drop of dilute hydrochloric acid typically fizzes. It occurs in sedimentary formations worldwide, especially former marine basins.
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