fossil

Fossiliferous Limestone Pebble

Calcite-rich Fossiliferous Marine Limestone

Hardness: 3 on the Mohs scale (calcite matrix). Color: Grey to brownish-grey host rock with lighter, whitish fossil fragments. Luster: Dull to earthy matrix with slightly vitreous fossilized shell fragments. Structure: Microcrystalline matrix containing preserved invertebrate skeletal remains.

Hardness: 3 on the Mohs scale (calcite matrix)

Identified July 26, 2026More fossil →

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Physical properties

Formation & geological history

Formed in warm, shallow marine environments through the accumulation and compaction of organic calcium carbonate debris (such as bryozoan, coral, crinoid, or shell fragments) along with fine carbonate mud, typically dating from Paleozoic to Mesozoic eras.

Uses & applications

Used primarily as educational specimens, items for beachcombers and fossil collectors, and occasionally in polished decorative stonework.

Geological facts

Beach-worn pebbles like this often expose cross-sections of ancient marine life that were naturally water-cut and smoothed by wave action over many years.

Field identification & locations

Look for rounded grey or tan pebbles along shores or riverbeds displaying clear lighter-colored organic or fan-like/patterned cross-sections. Testing with diluted acid causes effervescence due to calcite content.

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