Bivalve Internal Mold Fossil
Steinkern (Mollusca: Bivalvia)
fossil
Category
Limestone
Browse limestone specimens identified by the Rock Identifier community.
Limestone with Fossil Fragment
Bioclastic limestone (Calcium carbonate, CaCO3)
sedimentary
Fossilized Bivalve in Limestone
Class Bivalvia within Sedimentary Matrix (likely CaCO3)
fossil
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Flint
Sedimentary cryptocrystalline quartz (SiO2)
sedimentary
Lapis Lazuli
Complex rock composed mainly of lazurite, calcite, and pyrite
gemstone
Flint
SiO2 (Microcrystalline Quartz)
sedimentary
Flint
SiO2 (Cryptocrystalline Quartz)
sedimentary
Lapis Lazuli
Lapis Lazuli (Rock composed mainly of lazurite, calcite, and pyrite)
gemstone
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Lapis Lazuli (or Sodalite)
Lapis Lazuli (principally Lazurite: Na6Ca2(Al6Si6O24)S2)
metamorphic
Lapis Lazuli
Lapis Lazuli (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2
metamorphic
Calcite
Calcium Carbonate (CaCO3)
mineral
Bivalve Fossil (Clam)
Class Bivalvia (e.g., Mercenaria or similar genus), composed of CaCO3 (Aragonite/Calcite)
fossil
Bivalve Fossil (Clam)
Class Bivalvia, likely Mercenaria or similar genus
fossil
Fossiliferous Limestone with Rugose Coral
Rugosa (order), typically preserved in CaCO3 (Calcite)
sedimentary
Fossiliferous Limestone (Coral Fossil)
Scleractinian Coral in Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous Limestone with Brachiopod
Limestone (Calcium Carbonate, CaCO3) with Phylum Brachiopoda fossil
sedimentary
Chert Nodules in Limestone
Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Sedimentary Rock (CaCO3)
sedimentary
Grey Limestone
Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)
sedimentary
Limestone Pebble
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous Limestone with Brachiopod
Phylum Brachiopoda in calcitic matrix
sedimentary
Cockle Shell Fossil
Cardiidae family (Bivalvia)
fossil
Fossilized Brachiopod Shell Fragment
Brachiopoda (Class: Rhynchonellata or Strophomenata)
fossil
Fossiliferous Chert or Limestone
Sedimentary rock containing fossilized marine invertebrates (likely crinoid stems or bryozoans)
sedimentary
Gastropod Fossil (Snail)
Gastropoda (Internal mold/Steinkern)
sedimentary
Land Snail Shell
Gastropoda (Calcium Carbonate, CaCO3)
fossil
Crushed Limestone
Calcium Carbonate (CaCO3)
Sedimentary
Chert (Nodule / Geode fragment)
Microcrystalline Quartz (SiO2)
sedimentary
Chalky Limestone
Carbonate sedimentary rock (CaCO3)
sedimentary
Green Onyx (Commercial Marble/Travertine)
CaCO3 (Calcite / Banded Limestone)
metamorphic
Quartz Geode in Sedimentary Host Rock
Silicon Dioxide (SiO2) in Carbonate Matrix
sedimentary
Limestone with Secondary Mineralization
Calcium Carbonate (CaCO3)
sedimentary
Fossil-bearing Sedimentary Rock
Sedimentum cum fossili
fossil
Weathered limestone cobble
Limestone, predominantly calcite (CaCO₃)
sedimentary
Weathered limestone fragment
Limestone, predominantly calcite (CaCO₃)
sedimentary
Fossiliferous Limestone
Limestone with embedded fossil cross-section
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossilized Gastropod / Coral
Phylum Mollusca / Cnidaria (Silicified or Calcified)
fossil
Brachiopod Fossil
Phylum Brachiopoda
fossil