Rock Identifier
Fossilized Brachiopod Shell Fragment (Brachiopoda (Class: Rhynchonellata or Strophomenata)) — fossil
fossil

Fossilized Brachiopod Shell Fragment

Brachiopoda (Class: Rhynchonellata or Strophomenata)

AI-generated identification · may be incorrect

Hardness: 3-4 (Calcite composition); Color: Off-white to grey; Luster: Dull/Earthy; Structure: Biconvex shell with radial ribs (costae); Cleavage: N/A (Fossilized structure)

Hardness
3-4 (Calcite composition)
Color
Off-white to grey
Luster
Dull/Earthy
Identified More fossil →
Explore Fossilized Brachiopod Shell Fragment in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App StoreGoogle Play

Physical properties

Hardness: 3-4 (Calcite composition); Color: Off-white to grey; Luster: Dull/Earthy; Structure: Biconvex shell with radial ribs (costae); Cleavage: N/A (Fossilized structure)

Formation & geological history

Formed through the process of permineralization or recrystallization of marine shells in sedimentary environments, typically Paleozoic or Mesozoic era (approx. 50-500 million years old)

Uses & applications

Educational collections, scientific study of paleoenvironments, and decorative fossil displays

Geological facts

Brachiopods are 'lamp shells' that have existed for over 500 million years; unlike clams which have left/right shells, brachiopods have top/bottom shells

Field identification & locations

Identify by symmetrical radial ribbing and the presence of a 'beak' or pedicle opening. Common in limestone and shale deposits globally

More like this

Other fossil specimens

Probable fossil-bearing rock or mineral concretion (Unidentified carbonate-rich concretion with a possible fossil inclusion) — fossil

Probable fossil-bearing rock or mineral concretion

Unidentified carbonate-rich concretion with a possible fossil inclusion

fossil
Likely fossil oyster shell (Fossilized bivalve shell; exact species cannot be identified from the image) — fossil

Likely fossil oyster shell

Fossilized bivalve shell; exact species cannot be identified from the image

fossil
Crinoid Stem Fossil in Matrix (Phylum Echinodermata, Class Crinoidea) — fossil

Crinoid Stem Fossil in Matrix

Phylum Echinodermata, Class Crinoidea

fossil
Fossiliferous limestone (likely a crinoidal or shell-fragment limestone) (Bioclastic limestone, composed chiefly of calcite (CaCO₃)) — sedimentary

Fossiliferous limestone (likely a crinoidal or shell-fragment limestone)

Bioclastic limestone, composed chiefly of calcite (CaCO₃)

sedimentary
Rounded sedimentary pebble (Likely micritic limestone or calcareous sandstone) — sedimentary

Rounded sedimentary pebble

Likely micritic limestone or calcareous sandstone

sedimentary
Chert with Fossil Brachiopod (Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion) — sedimentary

Chert with Fossil Brachiopod

Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion

sedimentary